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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 matches(self, a, b, **config):
 """ The message must match by username """

        submitter_a = a['msg']['override']['submitter']['name']
        submitter_b = b['msg']['override']['submitter']['name']
        if submitter_a != submitter_b:
            return False
        return True