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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 build_absolute_uri(request, relative_url):
 """Ensure absolute_uri are relative to WEBROOT."""

    webroot = getattr(settings, 'WEBROOT', '')
    if webroot.endswith("/") and relative_url.startswith("/"):
        webroot = webroot[:-1]

    return request.build_absolute_uri(webroot + relative_url)