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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 readall_fast(stm, size):
 """ Slightly faster version of readall, it reads no more than two chunks. Meaning that it can only be used to read small data that doesn't span more that two packets. :param stm: Stream to read from, should have read method. :param size: Number of bytes to read. :return: """

    buf, offset = stm.read_fast(size)
    if len(buf) - offset < size:
        # slow case
        buf = buf[offset:]
        buf += stm.recv(size - len(buf))
        return buf, 0
    return buf, offset