sys:1: MatplotlibDeprecationWarning: Passing the fontdict parameter of _set_ticklabels() positionally is deprecated since Matplotlib 3.3; the parameter will become keyword-only two minor releases later.
sys:1: UserWarning: FixedFormatter should only be used together with FixedLocator
sys:1: MatplotlibDeprecationWarning: Case-insensitive properties were deprecated in 3.3 and support will be removed two minor releases later
These are not used internally within PyPlot, so it sounds like you have a plotting script that is using deprecated Matplotlib features. You should update your script.
Whenever I plot, I receive the following warning: