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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 is_feasible(self, solution):
 """Returns True if the given solution's derivatives may have potential valid, complete solutions. """

        newvars = solution.new.keys()
        for newvar in newvars:
            for c in self._constraints_for_var.get(newvar, []):
                values = c.extract_values(solution, use_defaults=True)
                if not c(*values):
                    return False
        return True