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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 __get_table_size(self):
 		""" 		Retrieve the size of the buffer needed by calling the method 		with a null pointer and length of zero. This should trigger an 		insufficient buffer error and return the size needed for the 		buffer. 		"""

		length = ctypes.wintypes.DWORD()
		res = self.method(None, length, False)
		if res != errors.ERROR_INSUFFICIENT_BUFFER:
			raise RuntimeError("Error getting table length (%d)" % res)
		return length.value