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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_logo_url(self, obj):
 """Get the community logo URL."""

        if current_app and obj.logo_url:
            return u'{site_url}{path}'.format(
                site_url=current_app.config.get('THEME_SITEURL'),
                path=obj.logo_url,
            )