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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 add_cors_headers(request, response):
 """Add cors headers needed for web app implementation."""

    response.headerlist.append(('Access-Control-Allow-Origin', '*'))
    response.headerlist.append(
        ('Access-Control-Allow-Methods', 'GET, OPTIONS'))
    response.headerlist.append(
        ('Access-Control-Allow-Headers',
         ','.join(DEFAULT_ACCESS_CONTROL_ALLOW_HEADERS)))