easy_install -U setuptoolsでRuntimeError: maximum recursion depth exceeded while calling a Python objectになった

easy_install -U setuptools
したら

# easy_install -U setuptools
Searching for setuptools
Reading https://pypi.python.org/simple/setuptools/
Best match: setuptools 34.2.0
Downloading https://pypi.python.org/packages/16/ef/44baff6e9b1f8125d759d026757677a8a82d14d9974726f13726dee9adfb/setuptools-34.2.0.zip#md5=41b630da4ea6cfa5894d9eb3142922be
Processing setuptools-34.2.0.zip
Writing /tmp/easy_install-ckKuPn/setuptools-34.2.0/setup.cfg
Running setuptools-34.2.0/setup.py -q bdist_egg --dist-dir /tmp/easy_install-ckKuPn/setuptools-34.2.0/egg-dist-tmp-fwNrcY
Traceback (most recent call last):
  File "/usr/bin/easy_install", line 9, in 
    load_entry_point('setuptools==0.9.8', 'console_scripts', 'easy_install')()
  File "/usr/lib/python2.7/site-packages/setuptools/command/easy_install.py", line 1992, in main
    with_ei_usage(lambda:
  File "/usr/lib/python2.7/site-packages/setuptools/command/easy_install.py", line 1979, in with_ei_usage
    return f()

省略

  File "/usr/lib/python2.7/site-packages/pkg_resources.py", line 814, in scan
    for dist in find_distributions(item):
  File "/usr/lib/python2.7/site-packages/pkg_resources.py", line 1958, in find_distributions
    importer = get_importer(path_item)
  File "/usr/lib64/python2.7/pkgutil.py", line 394, in get_importer
    importer = ImpImporter(path_item)
RuntimeError: maximum recursion depth exceeded while calling a Python object

となった・・

pip install --upgrade distribute

を実行したらなんとかなった

python難しい・・