<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
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<USER_TASK:>
Description:
 def get_bio(tweet):
 """ Get the bio text of the user who posted the Tweet Args: tweet (Tweet):
 A Tweet object (or a dictionary) Returns: str: the bio text of the user who posted the Tweet In a payload the abscence of a bio seems to be represented by an empty string or a None, this getter always returns a string (so, empty string if no bio is available). Example: 'Niche millenial content aggregator' 'Niche millenial content aggregator' """


    if is_original_format(tweet):
        bio_or_none = tweet["user"].get("description", "")
    else:
        bio_or_none = tweet["actor"].get("summary", "")
    if bio_or_none is None:
        return ""
    else:
        return bio_or_none