MSMetaEnhancer: A Python package for mass spectra metadata annotation

MSMetaEnhancer is a Python software package for the metadata enrichment of records in mass spectral library files commonly used as reference for chemical identification via mass spectrometry.
Each record contains spectral information, i.e., peak mass to charge ratio (m/z) and intensities, alongside chemical & structural metadata, e.g., identifiers.
The package uses matchms for data IO and supports the open, text-based `.msp` format.
It annotates given mass spectra records in the library file by adding missing metadata such as SMILES, InChI, and CAS numbers to the individual entries.
The package retrieves the respective information by querying several external databases using existing metadata (e.g., SMILES or CAS number), converting different representations or database identifiers.
Multiple databases and services are included, currently supporting the chemical identifier resolver (CIR), chemical translation service (CTS), ChemIDplus, the Integrated Database for Small Molecules (IDSM) , PubChem, and BridgeDB.
Additionally, instead of querying external databases, computing the identifiers is also supported (e.g. molecular weight from SMILES).