Can't import 'inspect' when 'using PyCall'

```
julia> using PyCall
[ Info: Recompiling stale cache file /home/duncan/.julia/compiled/v1.2/PyCall/GkzkC.ji for PyCall [438e738f-606a-5dbb-bf0a-cddfbfd45ab0]
ERROR: InitError: PyError (PyImport_ImportModule

...etc...

)
ImportError('No module named inspect',)

Stacktrace:
[1] pyimport(::String) at /home/duncan/.julia/packages/PyCall/ttONZ/src/PyCall.jl:544
[2] __init__() at /home/duncan/.julia/packages/PyCall/ttONZ/src/pyinit.jl:202
[3] _include_from_serialized(::String, ::Array{Any,1}) at ./loading.jl:685
[4] _require_from_serialized(::String) at ./loading.jl:736
[5] _require(::Base.PkgId) at ./loading.jl:1023
[6] require(::Base.PkgId) at ./loading.jl:911
[7] require(::Module, ::Symbol) at ./loading.jl:906
during initialization of module PyCall
```

I've already set my `ENV["PYTHON"]` to the proper path, and I've verified that using that python binary, I can `import inspect`.