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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 calculate_single_terms(self):
 """Apply all methods stored in the hidden attribute `PART_ODE_METHODS`. q(0.25) """

        self.numvars.nmb_calls = self.numvars.nmb_calls+1
        for method in self.PART_ODE_METHODS:
            method(self)