@in_place_transformation<EOL>def enrich_pubmed_citations(graph: BELGraph, manager: Manager) -> Set[str]:
pmids = get_pubmed_identifiers(graph)<EOL>pmid_data, errors = get_citations_by_pmids(manager=manager, pmids=pmids)<EOL>for u, v, k in filter_edges(graph, has_pubmed):<EOL><INDENT>pmid = graph[u][v][k][CITATION][CITATION_REFERENCE].strip()<EOL>if pmid not in pmid_data:<EOL><INDENT>log.warning('<STR_LIT>', pmid)<EOL>errors.add(pmid)<EOL>continue<EOL><DEDENT>graph[u][v][k][CITATION].update(pmid_data[pmid])<EOL><DEDENT>return errors<EOL>
Overwrite all PubMed citations with values from NCBI's eUtils lookup service.

    :return: A set of PMIDs for which the eUtils service crashed