https://stackoverflow.com/search?q=%5Bpip%5D+install+square+brackets
– phdFeb 13 '20 at 15:13
BTW, that's buggy -- it should be quoted as `pip install -e '.[all,postgresql]'`; without the quotes, if you have any files in your current directory named something like `.a` or `.l`, the `.[all,postgresql]` will be replaced with a list of matching filenames by the shell before `pip` is started.
– Charles DuffyFeb 13 '20 at 15:55
Thanks. Actually I understand the usage of square brackets. I only don't know the usage of "all". Obviously there is no package named "all". And I could not get a clear answer from the other related questions.
– cd20Feb 14 '20 at 08:19