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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 find_model_by_id(self, constructor, id_, *, columns=None):
 """Searches for a model by id, according to its class' primary_key_name. If primary_key_name is a tuple, id_ must be a tuple with a matching length. """

    return self.find_model(
      constructor, get_id_constraints(constructor.primary_key_name, id_), columns=columns)