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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 operator(self):
 """Get the function operator from his name :return callable: a callable to make operation on a column """

        operators = (self.op, self.op + '_', '__' + self.op + '__')

        for op in operators:
            if hasattr(self.column, op):
                return op

        raise InvalidFilters("{} has no operator {}".format(self.column.key, self.op))