$ pip freeze --all
appdirs==1.4.3
distlib==0.3.0
filelock==3.0.12
importlib-metadata==1.5.0
pip==20.0.2
setuptools==45.2.0
six==1.14.0
virtualenv==20.0.2
wheel==0.34.2
zipp==2.2.0

$ virtualenv vvv -p python2.7 -vvv
72 setup logging to NOTSET [DEBUG report:43]
77 find interpreter for spec PythonSpec(implementation=CPython, major=2, minor=7) [INFO builtin:44]
77 discover system for PythonInfo(spec=CPython3.7.2.final.0-64, exe=/private/tmp/venv/bin/python3, platform=darwin, version='3.7.2 (v3.7.2:9a3ffc0492, Dec 24 2018, 02:44:43) \n[Clang 6.0 (clang-600.0.57)]', encoding_fs_io=utf-8-UTF-8) in /Library/Frameworks/Python.framework/Versions/3.7 [DEBUG py_info:332]
79 filesystem is not case-sensitive [DEBUG info:28]
80 Attempting to acquire lock 4513505352 on /Users/asottile/Library/Application Support/virtualenv/py-info/20.0.2/fb7ec9939e66e8ed189e2fe772cae61fcc992510c23be22bd7dadeab5367beb4.lock [DEBUG filelock:270]
80 Lock 4513505352 acquired on /Users/asottile/Library/Application Support/virtualenv/py-info/20.0.2/fb7ec9939e66e8ed189e2fe772cae61fcc992510c23be22bd7dadeab5367beb4.lock [INFO filelock:274]
80 get interpreter info via cmd: /Library/Frameworks/Python.framework/Versions/3.7/python -s /private/tmp/venv/lib/python3.7/site-packages/virtualenv/discovery/py_info.py [DEBUG cached_py_info:107]
82 Attempting to release lock 4513505352 on /Users/asottile/Library/Application Support/virtualenv/py-info/20.0.2/fb7ec9939e66e8ed189e2fe772cae61fcc992510c23be22bd7dadeab5367beb4.lock [DEBUG filelock:315]
82 Lock 4513505352 released on /Users/asottile/Library/Application Support/virtualenv/py-info/20.0.2/fb7ec9939e66e8ed189e2fe772cae61fcc992510c23be22bd7dadeab5367beb4.lock [INFO filelock:318]
82 failed to query /Library/Frameworks/Python.framework/Versions/3.7/python with code 8 err: 'Exec format error' [INFO cached_py_info:39]
83 done in 80ms [INFO __main__:24]
83 RuntimeError: failed to detect cpython3.7.2-64|cpython3.7.2|cpython3.7-64|cpython3.7|cpython3-64|cpython3|cpython-64|cpython|python3.7.2-64|python3.7.2|python3.7-64|python3.7|python3-64|python3|python-64|python in /Library/Frameworks/Python.framework/Versions/3.7 [ERROR __main__:36]