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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 from_clauses(self, clauses):
 """ This methods copies a list of clauses into a CNF object. :param clauses: a list of clauses. :type clauses: list(list(int)) Example: .. code-block:: python [[-1, 2], [1, -2], [5]] 5 """


        self.clauses = copy.deepcopy(clauses)

        for cl in self.clauses:
            self.nv = max([abs(l) for l in cl] + [self.nv])