Typical discord session, helping someone past the "I just installed my package with pip, but python doesn't see it" problem

gistfile1.txt

[7:24 AM]Deleted User: I downloaded a plugin via pip but Python doesn't recognize it
 — 01/24/2021 7:24 AM
[7:25 AM]offby1: you have two or more versions of python installed
[7:26 AM]offby1: you used one of them to install the package, and are now using the other to try to run it.  This doesn't work.
[7:26 AM]offby1: figure out which version you're running now, and use that version to install the package again
[7:26 AM]Deleted User: I have Python 3.9
[7:26 AM]Deleted User: I just downloaded it because my C drive got wiped
[7:26 AM]offby1: I will bet you you also have some other version as well
[7:27 AM]offby1: what exactly did you type originally when you ran pip?
[7:27 AM]Deleted User: pip install pychroma
[7:27 AM]offby1: can you run that command again, and capture the output, and paste it (preferably as text, not an image)
[7:28 AM]offby1: I suspect that ran some older version of python but would like to see
[7:28 AM]Deleted User:
C:\Users\gastg>pip install pychroma
Requirement already satisfied: pychroma in c:\users\gastg\appdata\local\programs\python\python39\lib\site-packages (0.0.2)
Requirement already satisfied: pynput>=1.6.8 in c:\users\gastg\appdata\local\programs\python\python39\lib\site-packages (from pychroma) (1.7.2)
Requirement already satisfied: requests>=2.23.0 in c:\users\gastg\appdata\local\programs\python\python39\lib\site-packages (from pychroma) (2.25.1)
Requirement already satisfied: six in c:\users\gastg\appdata\local\programs\python\python39\lib\site-packages (from pynput>=1.6.8->pychroma) (1.15.0)
Requirement already satisfied: idna<3,>=2.5 in c:\users\gastg\appdata\local\programs\python\python39\lib\site-packages (from requests>=2.23.0->pychroma) (2.10)
Requirement already satisfied: certifi>=2017.4.17 in c:\users\gastg\appdata\local\programs\python\python39\lib\site-packages (from requests>=2.23.0->pychroma) (2020.12.5)
Requirement already satisfied: chardet<5,>=3.0.2 in c:\users\gastg\appdata\local\programs\python\python39\lib\site-packages (from requests>=2.23.0->pychroma) (4.0.0)
Requirement already satisfied: urllib3<1.27,>=1.21.1 in c:\users\gastg\appdata\local\programs\python\python39\lib\site-packages (from requests>=2.23.0->pychroma) (1.26.2)
[7:28 AM]offby1: thanks!!
[7:28 AM]offby1: oh, it sure looks like python39 😐
[7:29 AM]offby1: ok, my next hypotheses: you're using an IDE that is using a virtualenv
[7:29 AM]Deleted User: I use Pycharm as IDE
[7:29 AM]offby1: yep
[7:29 AM]Deleted User: I think so
[7:29 AM]offby1: in the program that's failing, can you put these lines at the very top, so that they'll run before your import fails:
import sys
print(sys.executable)
[7:29 AM]offby1: then run it and tell me what it says
[7:30 AM]Deleted User:
"E:\Programme\PyCharm\Python Projects\RazerChroma-Python\venv\Scripts\python.exe" "E:/Programme/PyCharm/Python Projects/RazerChroma-Python/main.py"
Traceback (most recent call last):
  File "E:\Programme\PyCharm\Python Projects\RazerChroma-Python\main.py", line 4, in <module>
    import pychroma
ModuleNotFoundError: No module named 'pychroma'
E:\Programme\PyCharm\Python Projects\RazerChroma-Python\venv\Scripts\python.exe

Process finished with exit code 1
[7:30 AM]offby1: I predict it will not be c:\users\gastg\appdata\local\programs\python\python39\bin\python.exe
[7:31 AM]offby1: yeah that's it
[7:31 AM]offby1: so ...
[7:31 AM]offby1: there's probably some official "pycharm" way to do it, but I bet this will work
c:\> "E:\Programme\PyCharm\Python Projects\RazerChroma-Python\venv\Scripts\python.exe" -m pip install pychroma
[7:32 AM]offby1: try dat, report back 🙂
[7:32 AM]Deleted User:
C:\Users\gastg>"E:\Programme\PyCharm\Python Projects\RazerChroma-Python\venv\Scripts\python.exe" -m pip install pychroma
Collecting pychroma
  Using cached pychroma-0.0.2-py3-none-any.whl (10 kB)
Collecting pynput>=1.6.8
  Using cached pynput-1.7.2-py2.py3-none-any.whl (99 kB)
Collecting requests>=2.23.0
  Using cached requests-2.25.1-py2.py3-none-any.whl (61 kB)
Collecting six
  Using cached six-1.15.0-py2.py3-none-any.whl (10 kB)
Collecting chardet<5,>=3.0.2
  Using cached chardet-4.0.0-py2.py3-none-any.whl (178 kB)
Collecting urllib3<1.27,>=1.21.1
  Using cached urllib3-1.26.2-py2.py3-none-any.whl (136 kB)
Collecting certifi>=2017.4.17
  Using cached certifi-2020.12.5-py2.py3-none-any.whl (147 kB)
Collecting idna<3,>=2.5
  Using cached idna-2.10-py2.py3-none-any.whl (58 kB)
Installing collected packages: urllib3, six, idna, chardet, certifi, requests, pynput, pychroma
Successfully installed certifi-2020.12.5 chardet-4.0.0 idna-2.10 pychroma-0.0.2 pynput-1.7.2 requests-2.25.1 six-1.15.0 urllib3-1.26.2
[7:32 AM]offby1: now try your program; I predict success
[7:33 AM]Deleted User: Yep, it recognizes it
[7:33 AM]offby1: 💐
[7:33 AM]Deleted User: And it uses the module
[7:33 AM]Deleted User: Thank you so much!
[7:33 AM]offby1: I should really save this session with you and add it to some FAQ somewhere ... people have this problem all the time