Python Error: No module named mrjob.job

Question

I am running the following simple script from the book and getting the following error

from mrjob.job import MRJob

class MRWordCount(MRJob):
 def mapper(self, _, line):
  for word in line.split():
   yield(word, 1)
 def reducer(self, word, counts):
  yield(word, sum(counts))

if __name__ == '__main__':
 MRWordCount.run()

Using cygwin64 on windows 10 it returns the following error:

User001@Ubuntu /cygdrive/c/Users/User001/PycharmProjects/TestProject
$ python preparation.py input.txt
Traceback (most recent call last):
  File "preparation.py", line 1, in <module>
    from mrjob.job import MRJob
ImportError: No module named mrjob.job

Here is what I did:

1. I installed mrjob using pip install mrjob and it installed successfully.

2. I have checked that files exist in site-packages/mrjob and job.py file also exist and I can open the file and see the methods inside that file.

3. I am using Pycharm so when I try to import mrjob it also gives me syntax completion that is pycharm recognizes where is the file.

Now I do not understand why it is unable to get this module. Can anybody help ? Thanks

Answer 1

From The Module Search Path.

When a module named spam is imported, the interpreter first searches for a built-in module with that name. If not found, it then searches for a file named spam.py in a list of directories given by the variable sys.path. sys.path is initialized from these locations:

• the directory containing the input script (or the current directory).
• PYTHONPATH (a list of directory names, with the same syntax as the shell variable PATH).
• the installation-dependent default.

Which means you should avoid naming your modules with the same name as standard-library or built-in module names. So you'd better rename your package name or script file name instead of mrjob.py.