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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 modified_lines_from_diff(self, diff):
 """Returns the changed lines in a diff. - Potentially this is vc specific (if not using udiff). Note: this returns the line numbers in descending order. """

        from pep8radius.diff import modified_lines_from_udiff
        for start, end in modified_lines_from_udiff(diff):
            yield start, end