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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 _reverse_call(self, related_method, *values):
 """ Convert each value to a related field, then call the method on each field, passing self.instance as argument. If related_method is a string, it will be the method of the related field. If it's a callable, it's a function which accept the related field and self.instance. """

        related_fields = self._to_fields(*values)
        for related_field in related_fields:
            if callable(related_method):
                related_method(related_field, self.instance._pk)
            else:
                getattr(related_field, related_method)(self.instance._pk)