**Added:**
- Add `to_smi` and `from_smi` in the IO module.
- Support filelike object in io module.
- Add kekulization to to_mol
**Changed:**
- Switch tests of the IO module to regular functions.
**Deprecated:**
- In the IO module, use `urlpath` instead of `file_uri` to follow
`fsspec` conventions.
**Fixed:**
- Fix bug in read_excel where sheet_name wasnt being used.
**Authors:**
- Emmanuel Noutahi
- Hadrien Mary