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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:
 async def _wait_for_data(self, current_command, number_of_bytes):
 """ This is a private utility method. This method accumulates the requested number of bytes and then returns the full command :param current_command: command id :param number_of_bytes: how many bytes to wait for :returns: command """

        while number_of_bytes:
            next_command_byte = await self.read()
            current_command.append(next_command_byte)
            number_of_bytes -= 1
        return current_command