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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_matching_service_template_file(service_name, template_files):
 """ Return the template file that goes with the given service name, or return None if there's no match. Subservices return the parent service's file. """

    # If this is a subservice, use the parent service's template
    service_name = service_name.split('.')[0]
    if service_name in template_files:
        return template_files[service_name]
    return None