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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 format_diff_pyxb(a_pyxb, b_pyxb):
 """Create a diff between two PyXB objects. Args: a_pyxb: PyXB object b_pyxb: PyXB object Returns: str : `Differ`-style delta """

    return '\n'.join(
        difflib.ndiff(
            serialize_to_xml_str(a_pyxb).splitlines(),
            serialize_to_xml_str(b_pyxb).splitlines(),
        )
    )