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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_string(val=None):
 """Force a string representation of an object Args: val: object to parse into a string Returns: str: String representation """

    if val is None:
        return ''
    if isinstance(val, list):
        newval = [str(x) for x in val]
        return ';'.join(newval)
    if isinstance(val, str):
        return val
    else:
        return str(val)