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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 force_list(val=None):
 """Force a list representation of an object Args: val: object to parse into a list Returns: """

    if val is None:
        return []
    if isinstance(val, pd.Series):
        return val.tolist()
    return val if isinstance(val, list) else [val]