Provides an interface to the 'PubChem' database via the PUG REST < https://pubchem.ncbi.nlm.nih.gov/docs/pug-rest> and PUG View < https://pubchem.ncbi.nlm.nih.gov/docs/pug-view> services. This package allows users to automatically access chemical and biological data from 'PubChem', including compounds, substances, assays, and various other data types. Functions are available to retrieve data in different formats, perform searches, and access detailed annotations.