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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 _num_values(self, vdr_dict):
        '''
        Returns the number of values in a record, using a given VDR
        dictionary. Multiplies the dimension sizes of each dimension,
        if it is varying.
        '''
        values = 1
        for x in range(0, vdr_dict['num_dims']):
            if (vdr_dict['dim_vary'][x] != 0):
                values = values * vdr_dict['dim_sizes'][x]
        return values