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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 _get_first_last(details):
 """ Gets a user's first and last name from details. """

    if "first_name" in details and "last_name" in details:
        return details["first_name"], details["last_name"]
    elif "first_name" in details:
        lst = details["first_name"].rsplit(" ", 1)
        if len(lst) == 2:
            return lst
        else:
            return lst[0], ""
    elif "last_name" in details:
        return "", details["last_name"]

    return "", ""