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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 _preparse(source, f=_compose(_replace_locals, _replace_booleans, _rewrite_assign, _clean_spaces_backtick_quoted_names)):
 """Compose a collection of tokenization functions Parameters source : str A Python source code string f : callable This takes a tuple of (toknum, tokval) as its argument and returns a tuple with the same structure but possibly different elements. Defaults to the composition of ``_rewrite_assign``, ``_replace_booleans``, and ``_replace_locals``. Returns ------- s : str Valid Python source code Notes ----- The `f` parameter can be any callable that takes *and* returns input of the form ``(toknum, tokval)``, where ``toknum`` is one of the constants from the ``tokenize`` module and ``tokval`` is a string. """

    assert callable(f), 'f must be callable'
    return tokenize.untokenize(lmap(f, tokenize_string(source)))