PyPlot needs to be reinstalled after Julia is interrupted

Hello,

I have Julia 1.2.0 installed with Plots. For installing PyPlot backend without manually installing Python, I followed the instructions in [https://github.com/JuliaPy/PyPlot.jl](url) and did:

`ENV["PYTHON"]=""`
`Pkg.build("PyCall")`
`Pkg.add("PyPlot")`
`using Plots`
`pyplot()`

Then, everything went fine. However, if I interrupt Julia (not with Ctrl+C, but, e.g., when the light suddenly turns off and the computer suddenly shuts down), when I execute Julia again, I receive the following message:

`error compiling __init__: could not load library "/tmp/lib/libpython3.7m.so.1.0"
/tmp/lib/libpython3.7m.so.1.0: cannot open shared object file: No such file or directory`

and I have to reinstall PyPlot with the commands above.

I have the same problem in two computers (one uses Debian Stretch, the other uses Ubuntu).