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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 diff(a, b):
 """Return the difference between two strings Will return a human-readable difference between two strings. See https://docs.python.org/3/library/difflib.html#difflib.Differ for more information about the output format Args: a (str):
 Original string b (str):
 New string Returns: `str` """

    return ''.join(
        Differ().compare(
            a.splitlines(keepends=True),
            b.splitlines(keepends=True)
        )
    )