no module named pip

python -m pip install -U pip

sudo apt-get install python3-pip

I guess either you didn't put any module in the target thing,
Or you spelled the module name wrong,

Or you tried to import a module from a different directory which somehow stuffed up.
If the 3rd one is the case, check this out:
https://stackoverflow.com/questions/2325923/how-to-fix-importerror-no-module-named-error-in-python

$ conda install -c anaconda nltk