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Python module to modify bytecode

Project Description

bytecode is a Python module to modify bytecode.

Install bytecode: pip install bytecode.

bytecode only works on Python 3.

Hello World

Example running print('Hello World!'):

from bytecode import Instr, Bytecode

bytecode = Bytecode()
bytecode.extend([Instr("LOAD_NAME", 'print'),
                 Instr("LOAD_CONST", 'Hello World!'),
                 Instr("CALL_FUNCTION", 1),
                 Instr("LOAD_CONST", None),
code = bytecode.to_code()


Hello World!


bytecode module version string: bytecode.__version__ (ex: '0.1').


  • Instr: abstract instruction, argument is not validated
  • ConcreteInstr: concrete instruction, argument must be an integer

Create instructions

  • Instr(name, arg=UNSET, *, lineno=None)
  • ConcreteInstr(name, arg=UNSET, *, lineno=None)
  • Instr.disassemble(code, offset)
  • ConcreteInstr.disassemble(code, offset)

Pseudo instructions

  • Label: target of jumps for Bytecode, must not be used in ConcreteBytecode
  • SetLineno: set the line number of following instructions


  • Bytecode: list of Instr
  • BytecodeBlocks: list of blocks, a block is a list of Instr and has a label
  • ConcreteBytecode: list of ConcreteInstr

Create bytecode

  • Bytecode.from_code(*, extended_arg_op=False)
  • BytecodeBlocks.from_code()
  • ConcreteBytecode.from_code()


  • bytecode.to_bytecode() -> Bytecode
  • bytecode.to_concrete_bytecode() -> ConcreteBytecode
  • bytecode.to_bytecode_blocks() -> BytecodeBlocks
  • bytecode.to_code() -> types.CodeType


  • 2016-02-26: Version 0.1
    • Rewrite completely the API!
  • 2016-02-23: Release 0.0
    • First public release
Release History

Release History

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File Name & Checksum SHA256 Checksum Help Version File Type Upload Date
bytecode-0.1-py3-none-any.whl (20.7 kB) Copy SHA256 Checksum SHA256 3.4 Wheel Feb 26, 2016
bytecode-0.1.tar.gz (15.4 kB) Copy SHA256 Checksum SHA256 Source Feb 26, 2016

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