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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_python_type(self, python_type):
 """Validate the possible combinations of python_type and type_name."""


        if python_type == 'bool':
            if self.variable:
                raise ArgumentError("You can only specify a bool python type on a scalar (non-array) type_name", type_name=self.type_name)

            return

        if python_type == 'string':
            if not (self.variable and self.unit_size == 1):
                raise ArgumentError("You can only pass a string python type on an array of 1-byte objects", type_name=self.type_name)

            return

        if python_type is not None:
            raise ArgumentError("You can only declare a bool or string python type.  Otherwise it must be passed as None", python_type=python_type)