DataCreate is a python script made to generate datapacks from 1.13.3 up to 1.19.4
$ python3 DataCreate.py
For exemple on Macos:
$ mv DataCreate.py datacreate$ chmod +x datacreate$ sudo mv datacreate /usr/local/bin
Reopen your terminal and you can now do $ datacreate to launch the program
If the file doesn't work as a command, it is maybe because you don't have a symlink pointing to your python3. To fix this do:
$ sudo ln -s $(which python3) /usr/local/bin/python3
This will create a symlink to your python3