App Engine dev server: bad runtime process port ['']

Question

I get following error message when I run the local dev server:

bad runtime process port ['']

Traceback (most recent call last):
  File "/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site.py", line 565, in <module>
    main()
  File "/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site.py", line 547, in main
    known_paths = addusersitepackages(known_paths)
  File "/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site.py", line 278, in addusersitepackages
    user_site = getusersitepackages()
  File "/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site.py", line 253, in getusersitepackages
    user_base = getuserbase() # this will also set USER_BASE
  File "/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site.py", line 242, in getuserbase
    from sysconfig import get_config_var
  File "/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/sysconfig.py", line 104, in <module>
    _PROJECT_BASE = os.path.dirname(_safe_realpath(sys.executable))
  File "/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/sysconfig.py", line 99, in _safe_realpath
    return realpath(path)
  File "/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/posixpath.py", line 366, in realpath
    if islink(component):
  File "/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/posixpath.py", line 136, in islink
    return stat.S_ISLNK(st.st_mode)
AttributeError: 'module' object has no attribute 'S_ISLNK'

I have tried to revert a couple of days and run the project in a well known working state, I get the same error. No problem to upload to google. Other projects work locally. I use the 1.8.1 SDK.

Answer 1

Ok, found the error. I should read the error message more closly. It states module has no attribute. And thats beacuse of name collision. I had a file called stat. Somehow even if I reverted the project the file was still around, don't know why.

Just renamed the file and everything works now again.

Answer 2

I had similar problems locally. I solved deleting all the files .pyc and reload page.