Since Conda.jl has pinned the miniconda version to 4.5.4 (JuliaPy/Conda.jl#124), I decided to use the default python distribution from python website (python-3.8.1-amd64). However, no matter what I do, I cannot get the Qt backend working.
After looking into the init.jl file in the repository, I found that
julia> using PyCall
julia> PyCall.pyexists("matplotlib.backends.backend_tkagg")
true
julia> PyCall.pyexists("matplotlib.backends.backend_qt5agg")
false
julia> PyCall.pyprogramname
"C:\\Users\\wangc\\AppData\\Local\\Programs\\Python\\Python38\\python.exe"
However, matplotlib.backends.backend_qt5agg can be imported from python:
PS C:\Users\wangc> C:\Users\wangc\AppData\Local\Programs\Python\Python38\python.exe
Python 3.8.1 (tags/v3.8.1:1b293b6, Dec 18 2019, 23:11:46) [MSC v.1916 64 bit (AMD64)] on win32
Type "help", "copyright", "credits" or "license" for more information.
>>> import matplotlib.backends.backend_qt5agg # success
Now I am not sure what to do next.