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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 spit(path, txt, encoding='UTF-8', append=False):
 """ Write a unicode string `txt` to file `path`. By default encoded as UTF-8 and truncates the file prior to writing Parameters path : str File path to file on disk txt : unicode Text content to write to file encoding : str, default `UTF-8`, optional Encoding of the file append : Boolean, default False Append to file instead of truncating before writing Returns ------- The txt written to the file as a unicode string """

    mode = 'a' if append else 'w'
    with io.open(path, mode, encoding=encoding) as f:
        f.write(txt)
        return txt