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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(address, length):
 """ Prepares an i2c read transaction. :param address: Slave address. :type: address: int :param length: Number of bytes to read. :type: length: int :return: New :py:class:`i2c_msg` instance for read operation. :rtype: :py:class:`i2c_msg` """

        arr = create_string_buffer(length)
        return i2c_msg(
            addr=address, flags=I2C_M_RD, len=length,
            buf=arr)