Add SMILES and molecular formula and weight (from https://github.com/…

[woodthom2]

…jaydugad/drug_named_entity_recognition/)

Description

Adding support for SMILES, mass, and molecular structure

Fixes # (issue)

Type of change

Please delete options that are not relevant.

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Requires a documentation revision

Testing

Please describe the tests that you ran to verify your changes. Provide instructions so we can reproduce. Please also list any relevant details for your test configuration

• test_formula.py
• test_mass.py
• test_smiles.py

Test Configuration

• Library version: 2.0.8
• OS: Ubuntu
• Toolchain: Pycharm

Checklist

• My PR is for one issue, rather than for multiple unrelated fixes.
• My code follows the style guidelines of this project. I have applied a Linter (recommended: Pycharm's code formatter) to make my whitespace consistent with the rest of the project.
• [ X] I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes
• Any dependent changes have been merged and published in downstream modules
• I have checked my code and corrected any misspellings
• I add third party dependencies only when necessary. If I changed the requirements, it changes in pyproject.toml
• If I introduced a new feature, I documented it ideally in the README examples so that people will know how to use it.