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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def walk_code(co, _prefix=''):
 """ Traverse a code object, finding all consts which are also code objects. Yields pairs of (name, code object). """

    name = _prefix + co.co_name
    yield name, co
    yield from chain.from_iterable(
        walk_code(c, _prefix=_extend_name(name, co))
        for c in co.co_consts
        if isinstance(c, CodeType)
    )