After investigating trouble reports from a couple of users, it appears there's a packaging issue with pyspedas 1.6.0 and 1.6.1. The released packages are missing the mms/feeps/sun directory and all the CSV files it contains. This seems to have started when the mission directories were moved to pyspedas/projects.
Fixed (hopefully!) in pyspedas 1.6.2. The MANIFEST.in file needed to be updated to reflect the new location of some items (mms/feeps/sun and a few other) that had been moved to pyspedas/projects.
After investigating trouble reports from a couple of users, it appears there's a packaging issue with pyspedas 1.6.0 and 1.6.1. The released packages are missing the mms/feeps/sun directory and all the CSV files it contains. This seems to have started when the mission directories were moved to pyspedas/projects.