code: def process_prefix(self, prefix: str) -> Union[Namespace, None]:
          
          if self.namespaces.get(prefix):
              return self.namespaces[prefix]
          iri: str = common_namespaces.get(prefix)
          if iri:
              return self.add_namespace(prefix, iri)
docs: Add namespace to graph if it has a local match
  
          This allows qnames to be used without adding their respected namespaces if they are in
          the common_namespaces local dict. This is is to save a butt-ton of time trying to see what
          the ontology has as far as uris go.
  
          Args: prefix: prefix of the uri in the rdflib namespace to be checked if it exists in
              the local dict of common_namespaces.
  
          Returns: Namespace of uri if add or already exists; else None