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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_icon_url(self, icon):
 """ Replaces the "icon name" with a full usable URL. * When the icon is an absolute URL, it is used as-is. * When the icon contains a slash, it is relative from the ``STATIC_URL``. * Otherwise, it's relative to the theme url folder. """

        if not icon.startswith('/') \
                and not icon.startswith('http://') \
                and not icon.startswith('https://'):
            if '/' in icon:
                return self.icon_static_root + icon
            else:
                return self.icon_theme_root + icon
        else:
            return icon