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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 _validate_type(self, name, obj, *args):
 """ Helper function that checks the input object type against each in a list of classes. This function also allows the input value to be equal to None. :param name: Name of the object. :param obj: Object to check the type of. :param args: List of classes. :raises TypeError: if the input object is not of any of the allowed types. """

        if obj is None:
            return
        for arg in args:
            if isinstance(obj, arg):
                return
        raise TypeError(self.__class__.__name__ + '.' + name + ' is of type ' + type(obj).__name__ +
                        '. Must be equal to None or one of the following types: ' + str(args))