Merge branch Davi0kProgramsThings:v3.0.3 into branch bitfinexcom:master.

[Davi0kProgramsThings]

Description

PR adds marker py.typed to the project.

See more: https://typing.readthedocs.io/en/latest/spec/distributing.html.

Motivation and Context

Related Issue

PR fixes the following issue: -

Type of change

• New feature (non-breaking change which adds functionality);

Checklist:

• I've done a self-review of my code;
• I've made corresponding changes to the documentation;
• I've made sure my changes generate no warnings;
• mypy returns no errors when run on the root package;

• I've run black to format my code;
• I've run isort to format my code's import statements;
• flake8 reports no errors when run on the entire code base;