all Python 3Strings (str)term

b"..." byte strings

bytes

Byte strings (b"...") hold a sequence of bytes rather than Unicode characters. Each item is an integer 0–255. Used when working with binary data.

Syntax

b"строка"  b'строка'

Indexing and slicing disagree on purpose: b[0] gives the integer 104, while b[0:1] gives back a bytes object, b'h'. Bytes never mix with str — b'a' + 'b' raises TypeError, and crossing between them goes through .encode() and .decode() with an encoding you have consciously chosen. Like str, bytes is immutable; when you need to patch bytes in place, reach for bytearray.

Examples

b = b"hello"; print(type(b))    # → <class 'bytes'>
print(b[0])                       # → 104
print(b"hello" + b" world")     # → b'hello world'
print(b"hi" * 3)                # → b'hihihi'
print(b"hello".decode("utf-8"))  # → hello
print("hello".encode("utf-8"))   # → b'hello'

See also

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