HelioPy is no longer developed

As of January 2022 HelioPy will no longer be developed or supported. Most of HelioPy's functionality is now implemented elsewhere:

Finding/loading in-situ data

sunpy version 3.1 (released October 2021) has support for reading CDF files. It also has functionality to search NASA's CDAWeb via. sunpy.net.Fido, which provides access to in-situ data from a large range of in-situ heliospheric observatories.

Generating spacecraft trajectories from SPICE kernels

The astrospice project re-implements all of this functionality, in a much more user and maintainer friendly codebase. It's currently actively developed, and accepting bug reports or feature requests.