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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 files_write(self, path, file, offset=0, create=False, truncate=False, count=None, **kwargs):
 """Writes to a mutable file in the MFS. .. code-block:: python b'' Parameters path : str Filepath within the MFS file : io.RawIOBase IO stream object with data that should be written offset : int Byte offset at which to begin writing at create : bool Create the file if it does not exist truncate : bool Truncate the file to size zero before writing count : int Maximum number of bytes to read from the source ``file`` """

        opts = {"offset": offset, "create": create, "truncate": truncate}
        if count is not None:
            opts["count"] = count
        kwargs.setdefault("opts", opts)

        args = (path,)
        body, headers = multipart.stream_files(file, self.chunk_size)
        return self._client.request('/files/write', args,
                                    data=body, headers=headers, **kwargs)