无法导入模块 Python 3 Windows

Question

Problem Description: When running scripts from the terminal (example: navigate to C:\\PythonPrograms\\ProjectName> and input file name so it looks like C:\\PythonPrograms\\ProjectName>main.py ), the script fails to run and an error message is received. For example, if a script includes import numpy , the error is ImportError: No module named numpy . When running from an IDE such as spyder, modules import correctly.

Modules were installed with Anaconda, and appear under C:\\Python37\\Lib\\site-packages

Systems : Windows 10 , Python 3.7.0

Code examples This script successfully runs:

 x = 1
 for i in range(10):
     print x
     x += 1


C:\Python Programs>test.py
1
2
3
4
5
6
7
8
9
10

This script does not run:

import serial
x = 1
for i in range(10):
    print x    
    x += 1


C:\Python Programs>test.py
Traceback (most recent call last):
  File "C:\Python Programs\test.py", line 1, in <module>
    import serial
ImportError: No module named serial

Edit: Python is added to the system path as shown: Screenclip

Solved!

Checked the path, it was all correct. Went to uninstall python and reinstall, discovered that there was an unknown python 2.7 installed, once it was uninstalled everything worked correctly.

Answer 1

You have to make sure that your Python Path Environment Variable is correctly set on your system.

This should look like

C:\Users\YOUR_USERNAME\AppData\Local\Programs\Python\Python37-32\

If it don't, try to reinstall Python and check Add Python 3.7 to PATH