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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(self):
 """ Reads STDIN until the end of input and returns a unicode string. """

        text = sys.stdin.read()

        # Decode the bytes returned from earlier Python STDIN implementations
        if sys.version_info[0] < 3 and text is not None:
            text = text.decode(sys.stdin.encoding or 'utf-8')

        return text