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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 prt_keys(self, prt, pre):
 """Print the alias for a relationship and its alias."""

        prt.write('{PRE}Relationship to parent: {ABC}\n'.format(
            PRE=pre, ABC=''.join(self.rel2chr.values())))
        for rel, alias in self.rel2chr.items():
            prt.write('{PRE}    {A} {DESC}\n'.format(PRE=pre, A=alias, DESC=rel))
        prt.write('\n{PRE}Relationship to child: {ABC}\n'.format(
            PRE=pre, ABC=''.join(self.rev2chr.values())))
        for rel, alias in self.rev2chr.items():
            prt.write('{PRE}    {A} {DESC}\n'.format(PRE=pre, A=alias, DESC=rel))