If you cannot execute the installed python package directly on OS X. Try:
python -m "package name" param / options
From python -h (help)
-m mod : run library module as a script (terminates option list)
eg.
python3 -m "jupyter" notebook
Please note that the python version may be different. If you installed jupyter with a different version of python, replace python3 with this version.
OS X python - 2,7x. .