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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 author_display(author, *args):
 """Returns either the linked or not-linked profile name."""


    # Call get_absolute_url or a function returning none if not defined
    url = getattr(author, 'get_absolute_url', lambda: None)()
    # get_short_name or unicode representation
    short_name = getattr(author, 'get_short_name', lambda: six.text_type(author))()
    if url:
        return mark_safe('<a href="{}">{}</a>'.format(url, short_name))
    else:
        return short_name