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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 read(self, pos, size, **kwargs):
 """ Reads some data from the file, storing it into memory. :param pos: The address to write the read data into memory :param size: The requested length of the read :return: The real length of the read """

        data, realsize = self.read_data(size, **kwargs)
        if not self.state.solver.is_true(realsize == 0):
            self.state.memory.store(pos, data, size=realsize)
        return realsize