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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 fsync(self, **kwargs):
 """Flush all pending writes to datafiles. :Parameters: Optional parameters can be passed as keyword arguments: - `lock`: If True lock the server to disallow writes. - `async`: If True don't block while synchronizing. .. warning:: `async` and `lock` can not be used together. .. warning:: MongoDB does not support the `async` option on Windows and will raise an exception on that platform. """

        self.admin.command("fsync",
                           read_preference=ReadPreference.PRIMARY, **kwargs)