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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_valid(self):
        '''checks if type is a valid type'''
        return (self.is_primitive and self.name) \
            or (self.is_complex and self.name) \
            or (self.is_list and self.nested) \
            or (self.is_map and self.nested) \
            or (self.is_model and self.nested)