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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 from_string(cls, string, format_=None, fps=None, **kwargs):
 """ Load subtitle file from string. See :meth:`SSAFile.load()` for full description. Arguments: string (str):
 Subtitle file in a string. Note that the string must be Unicode (in Python 2). Returns: SSAFile Example: """

        fp = io.StringIO(string)
        return cls.from_file(fp, format_, fps=fps, **kwargs)