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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 to_file(self, fp, format_, fps=None, **kwargs):
 """ Write subtitle file to file object. See :meth:`SSAFile.save()` for full description. Note: This is a low-level method. Usually, one of :meth:`SSAFile.save()` or :meth:`SSAFile.to_string()` is preferable. Arguments: fp (file object):
 A file object, ie. :class:`io.TextIOBase` instance. Note that the file must be opened in text mode (as opposed to binary). """

        impl = get_format_class(format_)
        impl.to_file(self, fp, format_, fps=fps, **kwargs)