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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 defverb(self, s1, p1, s2, p2, s3, p3):
 """ Set the verb plurals for s1, s2 and s3 to p1, p2 and p3 respectively. Where 1, 2 and 3 represent the 1st, 2nd and 3rd person forms of the verb. """

        self.checkpat(s1)
        self.checkpat(s2)
        self.checkpat(s3)
        self.checkpatplural(p1)
        self.checkpatplural(p2)
        self.checkpatplural(p3)
        self.pl_v_user_defined.extend((s1, p1, s2, p2, s3, p3))
        return 1