CategoriesDataFrame     CategoriesDataFrame objects
enrich                  Return functional enrichment of gene Entrez
                        IDs.
lookup                  Return integer Entrez IDs from gene symbols,
                        ensembl references, etc.
lookup_pubchem          Return table of drug identifiers to PubChem
                        CIDs.
lookup_pubchem_         Convert identifiers of a single ToppGene drug
                        database to PubChem CIDs.
