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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 combo_serve(request, path, client):
 """ Handles generating a 'combo' file for the given path. This is similar to what happens when we upload to S3. Processors are applied, and we get the value that we would if we were serving from S3. This is a good way to make sure combo files work as intended before rolling out to production. """

    joinfile = path
    sourcefiles = msettings['JOINED'][path]
    # Generate the combo file as a string.
    combo_data, dirname = combine_files(joinfile, sourcefiles, client)
    
    if path.endswith('.css'):
        mime_type = 'text/css'
    elif joinfile.endswith('.js'):
        mime_type = 'application/javascript'

    return HttpResponse(combo_data, mimetype=mime_type)