uuid.py 文件源码

def uuid4():
    """Generate a random UUID."""

    # When the system provides a version-4 UUID generator, use it.
    if _uuid_generate_random:
        _buffer = ctypes.create_string_buffer(16)
        _uuid_generate_random(_buffer)
        return UUID(bytes=_buffer.raw)

    # Otherwise, get randomness from urandom or the 'random' module.
    try:
        import os
        return UUID(bytes=os.urandom(16), version=4)
    except:
        import random
        bytes = [chr(random.randrange(256)) for i in range(16)]
        return UUID(bytes=bytes, version=4)