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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 frog_to_saf(tokens):
 """ Convert frog tokens into a new SAF document """

    tokens = [_add_pos1(token) for token in tokens]
    module = {'module': "frog",
              "started": datetime.datetime.now().isoformat()}
    return {"header": {'format': "SAF",
                       'format-version': "0.0",
                       'processed': [module]
                       }, "tokens": tokens}