diff --git a/parser/src/lexer.rs b/parser/src/lexer.rs
index edf21c973c..561ea4d772 100644
--- a/parser/src/lexer.rs
+++ b/parser/src/lexer.rs
@@ -540,8 +540,12 @@ where
         let end_pos = self.get_pos();
 
         let tok = if is_bytes {
-            Tok::Bytes {
-                value: string_content.as_bytes().to_vec(),
+            if string_content.is_ascii() {
+                Tok::Bytes {
+                    value: string_content.as_bytes().to_vec(),
+                }
+            } else {
+                return Err(LexicalError::StringError);
             }
         } else {
             Tok::String {
diff --git a/tests/snippets/bytes.py b/tests/snippets/bytes.py
index 19ebef68ae..0ffbc29f8c 100644
--- a/tests/snippets/bytes.py
+++ b/tests/snippets/bytes.py
@@ -1,6 +1,129 @@
-assert b'foobar'.__eq__(2) == NotImplemented
-assert b'foobar'.__ne__(2) == NotImplemented
-assert b'foobar'.__gt__(2) == NotImplemented
-assert b'foobar'.__ge__(2) == NotImplemented
-assert b'foobar'.__lt__(2) == NotImplemented
-assert b'foobar'.__le__(2) == NotImplemented
+from testutils import assertRaises
+
+# new
+assert bytes([1, 2, 3])
+assert bytes((1, 2, 3))
+assert bytes(range(4))
+assert bytes(3)
+assert b"bla"
+assert bytes("bla", "utf8")
+with assertRaises(TypeError):
+    bytes("bla")
+
+
+a = b"abcd"
+b = b"ab"
+c = b"abcd"
+
+#
+# repr
+assert repr(bytes([0, 1, 2])) == repr(b"\x00\x01\x02")
+assert repr(
+    bytes([0, 1, 9, 10, 11, 13, 31, 32, 33, 89, 120, 255])
+    == "b'\\x00\\x01\\t\\n\\x0b\\r\\x1f !Yx\\xff'"
+)
+assert repr(b"abcd") == "b'abcd'"
+
+# len
+assert len(bytes("abcdé", "utf8")) == 6
+
+# comp
+assert a == b"abcd"
+assert a > b
+assert a >= b
+assert b < a
+assert b <= a
+
+assert b"foobar".__eq__(2) == NotImplemented
+assert b"foobar".__ne__(2) == NotImplemented
+assert b"foobar".__gt__(2) == NotImplemented
+assert b"foobar".__ge__(2) == NotImplemented
+assert b"foobar".__lt__(2) == NotImplemented
+assert b"foobar".__le__(2) == NotImplemented
+
+# hash
+hash(a) == hash(b"abcd")
+
+# iter
+[i for i in b"abcd"] == ["a", "b", "c", "d"]
+assert list(bytes(3)) == [0, 0, 0]
+
+# add
+assert a + b == b"abcdab"
+
+# contains
+assert b"ab" in b"abcd"
+assert b"cd" in b"abcd"
+assert b"abcd" in b"abcd"
+assert b"a" in b"abcd"
+assert b"d" in b"abcd"
+assert b"dc" not in b"abcd"
+assert 97 in b"abcd"
+assert 150 not in b"abcd"
+with assertRaises(ValueError):
+    350 in b"abcd"
+
+
+# getitem
+d = b"abcdefghij"
+
+assert d[1] == 98
+assert d[-1] == 106
+assert d[2:6] == b"cdef"
+assert d[-6:] == b"efghij"
+assert d[1:8:2] == b"bdfh"
+assert d[8:1:-2] == b"igec"
+
+
+# is_xx methods
+
+assert bytes(b"1a23").isalnum()
+assert not bytes(b"1%a23").isalnum()
+
+assert bytes(b"abc").isalpha()
+assert not bytes(b"abc1").isalpha()
+
+# travis doesn't like this
+# assert bytes(b'xyz').isascii()
+# assert not bytes([128, 157, 32]).isascii()
+
+assert bytes(b"1234567890").isdigit()
+assert not bytes(b"12ab").isdigit()
+
+l = bytes(b"lower")
+b = bytes(b"UPPER")
+
+assert l.islower()
+assert not l.isupper()
+assert b.isupper()
+assert not bytes(b"Super Friends").islower()
+
+assert bytes(b" \n\t").isspace()
+assert not bytes(b"\td\n").isspace()
+
+assert b.isupper()
+assert not b.islower()
+assert l.islower()
+assert not bytes(b"tuPpEr").isupper()
+
+assert bytes(b"Is Title Case").istitle()
+assert not bytes(b"is Not title casE").istitle()
+
+# upper lower
+l = bytes(b"lower")
+b = bytes(b"UPPER")
+assert l.lower().islower()
+assert b.upper().isupper()
+
+# hex from hex
+assert bytes([0, 1, 9, 23, 90, 234]).hex() == "000109175aea"
+
+bytes.fromhex("62 6c7a 34350a ") == b"blz45\n"
+try:
+    bytes.fromhex("62 a 21")
+except ValueError as e:
+    str(e) == "non-hexadecimal number found in fromhex() arg at position 4"
+try:
+    bytes.fromhex("6Z2")
+except ValueError as e:
+    str(e) == "non-hexadecimal number found in fromhex() arg at position 1"
diff --git a/vm/src/obj/mod.rs b/vm/src/obj/mod.rs
index 0419d827f0..c824e726d8 100644
--- a/vm/src/obj/mod.rs
+++ b/vm/src/obj/mod.rs
@@ -3,6 +3,7 @@
 pub mod objbool;
 pub mod objbuiltinfunc;
 pub mod objbytearray;
+pub mod objbyteinner;
 pub mod objbytes;
 pub mod objclassmethod;
 pub mod objcode;
diff --git a/vm/src/obj/objbyteinner.rs b/vm/src/obj/objbyteinner.rs
new file mode 100644
index 0000000000..532504b028
--- /dev/null
+++ b/vm/src/obj/objbyteinner.rs
@@ -0,0 +1,349 @@
+use crate::pyobject::PyObjectRef;
+
+use crate::function::OptionalArg;
+
+use crate::vm::VirtualMachine;
+
+use crate::pyobject::{PyResult, TypeProtocol};
+
+use crate::obj::objstr::PyString;
+use std::collections::hash_map::DefaultHasher;
+use std::hash::{Hash, Hasher};
+
+use super::objint;
+use super::objsequence::PySliceableSequence;
+use crate::obj::objint::PyInt;
+use num_traits::ToPrimitive;
+
+#[derive(Debug, Default, Clone)]
+pub struct PyByteInner {
+    pub elements: Vec<u8>,
+}
+
+impl PyByteInner {
+    pub fn new(
+        val_option: OptionalArg<PyObjectRef>,
+        enc_option: OptionalArg<PyObjectRef>,
+        vm: &VirtualMachine,
+    ) -> PyResult<PyByteInner> {
+        // First handle bytes(string, encoding[, errors])
+        if let OptionalArg::Present(enc) = enc_option {
+            if let OptionalArg::Present(eval) = val_option {
+                if let Ok(input) = eval.downcast::<PyString>() {
+                    if let Ok(encoding) = enc.clone().downcast::<PyString>() {
+                        if &encoding.value.to_lowercase() == "utf8"
+                            || &encoding.value.to_lowercase() == "utf-8"
+                        // TODO: different encoding
+                        {
+                            return Ok(PyByteInner {
+                                elements: input.value.as_bytes().to_vec(),
+                            });
+                        } else {
+                            return Err(
+                                vm.new_value_error(format!("unknown encoding: {}", encoding.value)), //should be lookup error
+                            );
+                        }
+                    } else {
+                        return Err(vm.new_type_error(format!(
+                            "bytes() argument 2 must be str, not {}",
+                            enc.class().name
+                        )));
+                    }
+                } else {
+                    return Err(vm.new_type_error("encoding without a string argument".to_string()));
+                }
+            } else {
+                return Err(vm.new_type_error("encoding without a string argument".to_string()));
+            }
+        // Only one argument
+        } else {
+            let value = if let OptionalArg::Present(ival) = val_option {
+                match_class!(ival.clone(),
+                    i @ PyInt => {
+                            let size = objint::get_value(&i.into_object()).to_usize().unwrap();
+                            Ok(vec![0; size])},
+                    _l @ PyString=> {return Err(vm.new_type_error("string argument without an encoding".to_string()));},
+                    obj => {
+                        let elements = vm.extract_elements(&obj).or_else(|_| {Err(vm.new_type_error(format!(
+                        "cannot convert {} object to bytes", obj.class().name)))});
+
+                        let mut data_bytes = vec![];
+                        for elem in elements.unwrap(){
+                            let v = objint::to_int(vm, &elem, 10)?;
+                            if let Some(i) = v.to_u8() {
+                                data_bytes.push(i);
+                            } else {
+                                return Err(vm.new_value_error("bytes must be in range(0, 256)".to_string()));
+                                }
+
+                            }
+                        Ok(data_bytes)
+                        }
+                )
+            } else {
+                Ok(vec![])
+            };
+            match value {
+                Ok(val) => Ok(PyByteInner { elements: val }),
+                Err(err) => Err(err),
+            }
+        }
+    }
+
+    pub fn repr(&self) -> PyResult<String> {
+        let mut res = String::with_capacity(self.elements.len());
+        for i in self.elements.iter() {
+            match i {
+                0..=8 => res.push_str(&format!("\\x0{}", i)),
+                9 => res.push_str("\\t"),
+                10 => res.push_str("\\n"),
+                13 => res.push_str("\\r"),
+                32..=126 => res.push(*(i) as char),
+                _ => res.push_str(&format!("\\x{:x}", i)),
+            }
+        }
+        Ok(res)
+    }
+
+    pub fn len(&self) -> usize {
+        self.elements.len()
+    }
+
+    pub fn is_empty(&self) -> bool {
+        self.elements.len() == 0
+    }
+
+    pub fn eq(&self, other: &PyByteInner, vm: &VirtualMachine) -> PyResult {
+        if self.elements == other.elements {
+            Ok(vm.new_bool(true))
+        } else {
+            Ok(vm.new_bool(false))
+        }
+    }
+
+    pub fn ge(&self, other: &PyByteInner, vm: &VirtualMachine) -> PyResult {
+        if self.elements >= other.elements {
+            Ok(vm.new_bool(true))
+        } else {
+            Ok(vm.new_bool(false))
+        }
+    }
+
+    pub fn le(&self, other: &PyByteInner, vm: &VirtualMachine) -> PyResult {
+        if self.elements <= other.elements {
+            Ok(vm.new_bool(true))
+        } else {
+            Ok(vm.new_bool(false))
+        }
+    }
+
+    pub fn gt(&self, other: &PyByteInner, vm: &VirtualMachine) -> PyResult {
+        if self.elements > other.elements {
+            Ok(vm.new_bool(true))
+        } else {
+            Ok(vm.new_bool(false))
+        }
+    }
+
+    pub fn lt(&self, other: &PyByteInner, vm: &VirtualMachine) -> PyResult {
+        if self.elements < other.elements {
+            Ok(vm.new_bool(true))
+        } else {
+            Ok(vm.new_bool(false))
+        }
+    }
+
+    pub fn hash(&self) -> usize {
+        let mut hasher = DefaultHasher::new();
+        self.elements.hash(&mut hasher);
+        hasher.finish() as usize
+    }
+
+    pub fn add(&self, other: &PyByteInner, _vm: &VirtualMachine) -> Vec<u8> {
+        let elements: Vec<u8> = self
+            .elements
+            .iter()
+            .chain(other.elements.iter())
+            .cloned()
+            .collect();
+        elements
+    }
+
+    pub fn contains_bytes(&self, other: &PyByteInner, vm: &VirtualMachine) -> PyResult {
+        for (n, i) in self.elements.iter().enumerate() {
+            if n + other.len() <= self.len()
+                && *i == other.elements[0]
+                && &self.elements[n..n + other.len()] == other.elements.as_slice()
+            {
+                return Ok(vm.new_bool(true));
+            }
+        }
+        Ok(vm.new_bool(false))
+    }
+
+    pub fn contains_int(&self, int: &PyInt, vm: &VirtualMachine) -> PyResult<PyObjectRef> {
+        if let Some(int) = int.as_bigint().to_u8() {
+            if self.elements.contains(&int) {
+                Ok(vm.new_bool(true))
+            } else {
+                Ok(vm.new_bool(false))
+            }
+        } else {
+            Err(vm.new_value_error("byte must be in range(0, 256)".to_string()))
+        }
+    }
+
+    pub fn getitem_int(&self, int: &PyInt, vm: &VirtualMachine) -> PyResult {
+        if let Some(idx) = self.elements.get_pos(int.as_bigint().to_i32().unwrap()) {
+            Ok(vm.new_int(self.elements[idx]))
+        } else {
+            Err(vm.new_index_error("index out of range".to_string()))
+        }
+    }
+
+    pub fn getitem_slice(&self, slice: &PyObjectRef, vm: &VirtualMachine) -> PyResult {
+        Ok(vm
+            .ctx
+            .new_bytes(self.elements.get_slice_items(vm, slice).unwrap()))
+    }
+
+    pub fn isalnum(&self, vm: &VirtualMachine) -> PyResult {
+        Ok(vm.new_bool(
+            !self.elements.is_empty()
+                && self
+                    .elements
+                    .iter()
+                    .all(|x| char::from(*x).is_alphanumeric()),
+        ))
+    }
+
+    pub fn isalpha(&self, vm: &VirtualMachine) -> PyResult {
+        Ok(vm.new_bool(
+            !self.elements.is_empty()
+                && self.elements.iter().all(|x| char::from(*x).is_alphabetic()),
+        ))
+    }
+
+    pub fn isascii(&self, vm: &VirtualMachine) -> PyResult {
+        Ok(vm.new_bool(
+            !self.elements.is_empty() && self.elements.iter().all(|x| char::from(*x).is_ascii()),
+        ))
+    }
+
+    pub fn isdigit(&self, vm: &VirtualMachine) -> PyResult {
+        Ok(vm.new_bool(
+            !self.elements.is_empty() && self.elements.iter().all(|x| char::from(*x).is_digit(10)),
+        ))
+    }
+
+    pub fn islower(&self, vm: &VirtualMachine) -> PyResult {
+        Ok(vm.new_bool(
+            !self.elements.is_empty()
+                && self
+                    .elements
+                    .iter()
+                    .filter(|x| !char::from(**x).is_whitespace())
+                    .all(|x| char::from(*x).is_lowercase()),
+        ))
+    }
+
+    pub fn isspace(&self, vm: &VirtualMachine) -> PyResult {
+        Ok(vm.new_bool(
+            !self.elements.is_empty()
+                && self.elements.iter().all(|x| char::from(*x).is_whitespace()),
+        ))
+    }
+
+    pub fn isupper(&self, vm: &VirtualMachine) -> PyResult {
+        Ok(vm.new_bool(
+            !self.elements.is_empty()
+                && self
+                    .elements
+                    .iter()
+                    .filter(|x| !char::from(**x).is_whitespace())
+                    .all(|x| char::from(*x).is_uppercase()),
+        ))
+    }
+
+    pub fn istitle(&self, vm: &VirtualMachine) -> PyResult {
+        if self.elements.is_empty() {
+            return Ok(vm.new_bool(false));
+        }
+
+        let mut iter = self.elements.iter().peekable();
+        let mut prev_cased = false;
+
+        while let Some(c) = iter.next() {
+            let current = char::from(*c);
+            let next = if let Some(k) = iter.peek() {
+                char::from(**k)
+            } else if current.is_uppercase() {
+                return Ok(vm.new_bool(!prev_cased));
+            } else {
+                return Ok(vm.new_bool(prev_cased));
+            };
+
+            let is_cased = current.to_uppercase().next().unwrap() != current
+                || current.to_lowercase().next().unwrap() != current;
+            if (is_cased && next.is_uppercase() && !prev_cased)
+                || (!is_cased && next.is_lowercase())
+            {
+                return Ok(vm.new_bool(false));
+            }
+
+            prev_cased = is_cased;
+        }
+
+        Ok(vm.new_bool(true))
+    }
+
+    pub fn lower(&self, _vm: &VirtualMachine) -> Vec<u8> {
+        self.elements.to_ascii_lowercase()
+    }
+
+    pub fn upper(&self, _vm: &VirtualMachine) -> Vec<u8> {
+        self.elements.to_ascii_uppercase()
+    }
+
+    pub fn hex(&self, vm: &VirtualMachine) -> PyResult {
+        let bla = self
+            .elements
+            .iter()
+            .map(|x| format!("{:02x}", x))
+            .collect::<String>();
+        Ok(vm.ctx.new_str(bla))
+    }
+
+    pub fn fromhex(string: String, vm: &VirtualMachine) -> Result<Vec<u8>, PyObjectRef> {
+        // first check for invalid character
+        for (i, c) in string.char_indices() {
+            if !c.is_digit(16) && !c.is_whitespace() {
+                return Err(vm.new_value_error(format!(
+                    "non-hexadecimal number found in fromhex() arg at position {}",
+                    i
+                )));
+            }
+        }
+
+        // strip white spaces
+        let stripped = string.split_whitespace().collect::<String>();
+
+        // Hex is evaluated on 2 digits
+        if stripped.len() % 2 != 0 {
+            return Err(vm.new_value_error(format!(
+                "non-hexadecimal number found in fromhex() arg at position {}",
+                stripped.len() - 1
+            )));
+        }
+
+        // parse even string
+        Ok(stripped
+            .chars()
+            .collect::<Vec<char>>()
+            .chunks(2)
+            .map(|x| x.to_vec().iter().collect::<String>())
+            .map(|x| u8::from_str_radix(&x, 16))
+            .map(|x| x.unwrap())
+            .collect::<Vec<u8>>())
+    }
+}
diff --git a/vm/src/obj/objbytes.rs b/vm/src/obj/objbytes.rs
index f24c9273c5..2c8edca6ab 100644
--- a/vm/src/obj/objbytes.rs
+++ b/vm/src/obj/objbytes.rs
@@ -1,27 +1,38 @@
-use std::cell::Cell;
-use std::collections::hash_map::DefaultHasher;
-use std::hash::{Hash, Hasher};
+use crate::obj::objint::PyInt;
+use crate::obj::objstr::PyString;
+use crate::vm::VirtualMachine;
+use core::cell::Cell;
 use std::ops::Deref;
 
-use num_traits::ToPrimitive;
-
 use crate::function::OptionalArg;
-use crate::pyobject::{PyContext, PyObjectRef, PyRef, PyResult, PyValue};
-use crate::vm::VirtualMachine;
+use crate::pyobject::{PyClassImpl, PyContext, PyObjectRef, PyRef, PyResult, PyValue};
 
-use super::objint;
+use super::objbyteinner::PyByteInner;
 use super::objiter;
+use super::objslice::PySlice;
 use super::objtype::PyClassRef;
 
-#[derive(Debug)]
+/// "bytes(iterable_of_ints) -> bytes\n\
+/// bytes(string, encoding[, errors]) -> bytes\n\
+/// bytes(bytes_or_buffer) -> immutable copy of bytes_or_buffer\n\
+/// bytes(int) -> bytes object of size given by the parameter initialized with null bytes\n\
+/// bytes() -> empty bytes object\n\nConstruct an immutable array of bytes from:\n  \
+/// - an iterable yielding integers in range(256)\n  \
+/// - a text string encoded using the specified encoding\n  \
+/// - any object implementing the buffer API.\n  \
+/// - an integer";
+#[pyclass(name = "bytes", __inside_vm)]
+#[derive(Clone, Debug)]
 pub struct PyBytes {
-    value: Vec<u8>,
+    inner: PyByteInner,
 }
 type PyBytesRef = PyRef<PyBytes>;
 
 impl PyBytes {
-    pub fn new(data: Vec<u8>) -> Self {
-        PyBytes { value: data }
+    pub fn new(elements: Vec<u8>) -> Self {
+        PyBytes {
+            inner: PyByteInner { elements },
+        }
     }
 }
 
@@ -29,7 +40,7 @@ impl Deref for PyBytes {
     type Target = [u8];
 
     fn deref(&self) -> &[u8] {
-        &self.value
+        &self.inner.elements
     }
 }
 
@@ -39,131 +50,180 @@ impl PyValue for PyBytes {
     }
 }
 
-// Binary data support
+pub fn get_value<'a>(obj: &'a PyObjectRef) -> impl Deref<Target = Vec<u8>> + 'a {
+    &obj.payload::<PyBytes>().unwrap().inner.elements
+}
 
-// Fill bytes class methods:
 pub fn init(context: &PyContext) {
-    let bytes_doc =
-        "bytes(iterable_of_ints) -> bytes\n\
-         bytes(string, encoding[, errors]) -> bytes\n\
-         bytes(bytes_or_buffer) -> immutable copy of bytes_or_buffer\n\
-         bytes(int) -> bytes object of size given by the parameter initialized with null bytes\n\
-         bytes() -> empty bytes object\n\nConstruct an immutable array of bytes from:\n  \
-         - an iterable yielding integers in range(256)\n  \
-         - a text string encoded using the specified encoding\n  \
-         - any object implementing the buffer API.\n  \
-         - an integer";
-
-    extend_class!(context, &context.bytes_type, {
-        "__new__" => context.new_rustfunc(bytes_new),
-        "__eq__" => context.new_rustfunc(PyBytesRef::eq),
-        "__lt__" => context.new_rustfunc(PyBytesRef::lt),
-        "__le__" => context.new_rustfunc(PyBytesRef::le),
-        "__gt__" => context.new_rustfunc(PyBytesRef::gt),
-        "__ge__" => context.new_rustfunc(PyBytesRef::ge),
-        "__hash__" => context.new_rustfunc(PyBytesRef::hash),
-        "__repr__" => context.new_rustfunc(PyBytesRef::repr),
-        "__len__" => context.new_rustfunc(PyBytesRef::len),
-        "__iter__" => context.new_rustfunc(PyBytesRef::iter),
-        "__doc__" => context.new_str(bytes_doc.to_string())
-    });
-
+    PyBytesRef::extend_class(context, &context.bytes_type);
+    let bytes_type = &context.bytes_type;
+    extend_class!(context, bytes_type, {
+"fromhex" => context.new_rustfunc(PyBytesRef::fromhex),
+});
     let bytesiterator_type = &context.bytesiterator_type;
     extend_class!(context, bytesiterator_type, {
-        "__next__" => context.new_rustfunc(PyBytesIteratorRef::next),
-        "__iter__" => context.new_rustfunc(PyBytesIteratorRef::iter),
-    });
-}
-
-fn bytes_new(
-    cls: PyClassRef,
-    val_option: OptionalArg<PyObjectRef>,
-    vm: &VirtualMachine,
-) -> PyResult<PyBytesRef> {
-    // Create bytes data:
-    let value = if let OptionalArg::Present(ival) = val_option {
-        let elements = vm.extract_elements(&ival)?;
-        let mut data_bytes = vec![];
-        for elem in elements.iter() {
-            let v = objint::to_int(vm, elem, 10)?;
-            data_bytes.push(v.to_u8().unwrap());
-        }
-        data_bytes
-    // return Err(vm.new_type_error("Cannot construct bytes".to_string()));
-    } else {
-        vec![]
-    };
-
-    PyBytes::new(value).into_ref_with_type(vm, cls)
+"__next__" => context.new_rustfunc(PyBytesIteratorRef::next),
+"__iter__" => context.new_rustfunc(PyBytesIteratorRef::iter),
+});
 }
 
+#[pyimpl(__inside_vm)]
 impl PyBytesRef {
-    fn eq(self, other: PyObjectRef, vm: &VirtualMachine) -> PyObjectRef {
-        if let Ok(other) = other.downcast::<PyBytes>() {
-            vm.ctx.new_bool(self.value == other.value)
-        } else {
-            vm.ctx.not_implemented()
+    #[pymethod(name = "__new__")]
+    fn bytes_new(
+        cls: PyClassRef,
+        val_option: OptionalArg<PyObjectRef>,
+        enc_option: OptionalArg<PyObjectRef>,
+        vm: &VirtualMachine,
+    ) -> PyResult<PyBytesRef> {
+        PyBytes {
+            inner: PyByteInner::new(val_option, enc_option, vm)?,
         }
+        .into_ref_with_type(vm, cls)
     }
 
-    fn ge(self, other: PyObjectRef, vm: &VirtualMachine) -> PyObjectRef {
-        if let Ok(other) = other.downcast::<PyBytes>() {
-            vm.ctx.new_bool(self.value >= other.value)
-        } else {
-            vm.ctx.not_implemented()
-        }
+    #[pymethod(name = "__repr__")]
+    fn repr(self, vm: &VirtualMachine) -> PyResult {
+        Ok(vm.new_str(format!("b'{}'", self.inner.repr()?)))
     }
 
-    fn gt(self, other: PyObjectRef, vm: &VirtualMachine) -> PyObjectRef {
-        if let Ok(other) = other.downcast::<PyBytes>() {
-            vm.ctx.new_bool(self.value > other.value)
-        } else {
-            vm.ctx.not_implemented()
-        }
+    #[pymethod(name = "__len__")]
+    fn len(self, _vm: &VirtualMachine) -> usize {
+        self.inner.len()
     }
 
-    fn le(self, other: PyObjectRef, vm: &VirtualMachine) -> PyObjectRef {
-        if let Ok(other) = other.downcast::<PyBytes>() {
-            vm.ctx.new_bool(self.value <= other.value)
-        } else {
-            vm.ctx.not_implemented()
-        }
+    #[pymethod(name = "__eq__")]
+    fn eq(self, other: PyObjectRef, vm: &VirtualMachine) -> PyResult {
+        match_class!(other,
+        bytes @ PyBytes => self.inner.eq(&bytes.inner, vm),
+        _  => Ok(vm.ctx.not_implemented()))
     }
 
-    fn lt(self, other: PyObjectRef, vm: &VirtualMachine) -> PyObjectRef {
-        if let Ok(other) = other.downcast::<PyBytes>() {
-            vm.ctx.new_bool(self.value < other.value)
-        } else {
-            vm.ctx.not_implemented()
-        }
+    #[pymethod(name = "__ge__")]
+    fn ge(self, other: PyObjectRef, vm: &VirtualMachine) -> PyResult {
+        match_class!(other,
+        bytes @ PyBytes => self.inner.ge(&bytes.inner, vm),
+        _  => Ok(vm.ctx.not_implemented()))
     }
-
-    fn len(self, _vm: &VirtualMachine) -> usize {
-        self.value.len()
+    #[pymethod(name = "__le__")]
+    fn le(self, other: PyObjectRef, vm: &VirtualMachine) -> PyResult {
+        match_class!(other,
+        bytes @ PyBytes => self.inner.le(&bytes.inner, vm),
+        _  => Ok(vm.ctx.not_implemented()))
     }
-
-    fn hash(self, _vm: &VirtualMachine) -> u64 {
-        let mut hasher = DefaultHasher::new();
-        self.value.hash(&mut hasher);
-        hasher.finish()
+    #[pymethod(name = "__gt__")]
+    fn gt(self, other: PyObjectRef, vm: &VirtualMachine) -> PyResult {
+        match_class!(other,
+        bytes @ PyBytes => self.inner.gt(&bytes.inner, vm),
+        _  => Ok(vm.ctx.not_implemented()))
     }
-
-    fn repr(self, _vm: &VirtualMachine) -> String {
-        // TODO: don't just unwrap
-        let data = String::from_utf8(self.value.clone()).unwrap();
-        format!("b'{}'", data)
+    #[pymethod(name = "__lt__")]
+    fn lt(self, other: PyObjectRef, vm: &VirtualMachine) -> PyResult {
+        match_class!(other,
+        bytes @ PyBytes => self.inner.lt(&bytes.inner, vm),
+        _  => Ok(vm.ctx.not_implemented()))
+    }
+    #[pymethod(name = "__hash__")]
+    fn hash(self, _vm: &VirtualMachine) -> usize {
+        self.inner.hash()
     }
 
+    #[pymethod(name = "__iter__")]
     fn iter(self, _vm: &VirtualMachine) -> PyBytesIterator {
         PyBytesIterator {
             position: Cell::new(0),
             bytes: self,
         }
     }
-}
 
-pub fn get_value<'a>(obj: &'a PyObjectRef) -> impl Deref<Target = Vec<u8>> + 'a {
-    &obj.payload::<PyBytes>().unwrap().value
+    #[pymethod(name = "__add__")]
+    fn add(self, other: PyObjectRef, vm: &VirtualMachine) -> PyResult {
+        match_class!(other,
+        bytes @ PyBytes => Ok(vm.ctx.new_bytes(self.inner.add(&bytes.inner, vm))),
+        _  => Ok(vm.ctx.not_implemented()))
+    }
+
+    #[pymethod(name = "__contains__")]
+    fn contains(self, needle: PyObjectRef, vm: &VirtualMachine) -> PyResult {
+        match_class!(needle,
+        bytes @ PyBytes => self.inner.contains_bytes(&bytes.inner, vm),
+        int @ PyInt => self.inner.contains_int(&int, vm),
+        obj  => Err(vm.new_type_error(format!("a bytes-like object is required, not {}", obj))))
+    }
+
+    #[pymethod(name = "__getitem__")]
+    fn getitem(self, needle: PyObjectRef, vm: &VirtualMachine) -> PyResult {
+        match_class!(needle,
+        int @ PyInt => self.inner.getitem_int(&int, vm),
+        slice @ PySlice => self.inner.getitem_slice(slice.as_object(), vm),
+        obj  => Err(vm.new_type_error(format!("byte indices must be integers or slices, not {}", obj))))
+    }
+
+    #[pymethod(name = "isalnum")]
+    fn isalnum(self, vm: &VirtualMachine) -> PyResult {
+        self.inner.isalnum(vm)
+    }
+
+    #[pymethod(name = "isalpha")]
+    fn isalpha(self, vm: &VirtualMachine) -> PyResult {
+        self.inner.isalpha(vm)
+    }
+
+    #[pymethod(name = "isascii")]
+    fn isascii(self, vm: &VirtualMachine) -> PyResult {
+        self.inner.isascii(vm)
+    }
+
+    #[pymethod(name = "isdigit")]
+    fn isdigit(self, vm: &VirtualMachine) -> PyResult {
+        self.inner.isdigit(vm)
+    }
+
+    #[pymethod(name = "islower")]
+    fn islower(self, vm: &VirtualMachine) -> PyResult {
+        self.inner.islower(vm)
+    }
+
+    #[pymethod(name = "isspace")]
+    fn isspace(self, vm: &VirtualMachine) -> PyResult {
+        self.inner.isspace(vm)
+    }
+
+    #[pymethod(name = "isupper")]
+    fn isupper(self, vm: &VirtualMachine) -> PyResult {
+        self.inner.isupper(vm)
+    }
+
+    #[pymethod(name = "istitle")]
+    fn istitle(self, vm: &VirtualMachine) -> PyResult {
+        self.inner.istitle(vm)
+    }
+
+    #[pymethod(name = "lower")]
+    fn lower(self, vm: &VirtualMachine) -> PyResult {
+        Ok(vm.ctx.new_bytes(self.inner.lower(vm)))
+    }
+
+    #[pymethod(name = "upper")]
+    fn upper(self, vm: &VirtualMachine) -> PyResult {
+        Ok(vm.ctx.new_bytes(self.inner.upper(vm)))
+    }
+
+    #[pymethod(name = "hex")]
+    fn hex(self, vm: &VirtualMachine) -> PyResult {
+        self.inner.hex(vm)
+    }
+
+    // #[pymethod(name = "fromhex")]
+    fn fromhex(string: PyObjectRef, vm: &VirtualMachine) -> PyResult {
+        match_class!(string,
+        s @ PyString => {
+        match PyByteInner::fromhex(s.to_string(), vm) {
+        Ok(x) => Ok(vm.ctx.new_bytes(x)),
+        Err(y) => Err(y)}},
+        obj => Err(vm.new_type_error(format!("fromhex() argument must be str, not {}", obj )))
+        )
+    }
 }
 
 #[derive(Debug)]
@@ -182,7 +242,7 @@ type PyBytesIteratorRef = PyRef<PyBytesIterator>;
 
 impl PyBytesIteratorRef {
     fn next(self, vm: &VirtualMachine) -> PyResult<u8> {
-        if self.position.get() < self.bytes.value.len() {
+        if self.position.get() < self.bytes.inner.len() {
             let ret = self.bytes[self.position.get()];
             self.position.set(self.position.get() + 1);
             Ok(ret)