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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 add_clause(self, clause, no_return=True):
 """ This method is used to add a single clause to the solver. An optional argument ``no_return`` controls whether or not to check the formula's satisfiability after adding the new clause. :param clause: an iterable over literals. :param no_return: check solver's internal formula and return the result, if set to ``False``. :type clause: iterable(int) :type no_return: bool :rtype: bool if ``no_return`` is set to ``False``. Note that a clause can be either a ``list`` of integers or another iterable type over integers, e.g. ``tuple`` or ``set`` among others. A usage example is the following: .. code-block:: python False """


        if self.solver:
            res = self.solver.add_clause(clause, no_return)
            if not no_return:
                return res