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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_stdin():
 """ Generator for reading from standard input in nonblocking mode. Other ways of reading from ``stdin`` in python waits, until the buffer is big enough, or until EOF character is sent. This functions yields immediately after each line. """

    line = sys.stdin.readline()
    while line:
        yield line
        line = sys.stdin.readline()