[MacPorts] #59789: explicit execution of pip3.7 results in pip from python 2.7

[MacPorts]

#59789: explicit execution of pip3.7 results in pip from python 2.7
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  Reporter:  duaneellissd  |      Owner:  (none)
      Type:  defect        |     Status:  new
  Priority:  Normal        |  Milestone:
 Component:  ports         |    Version:  2.6.2
Resolution:                |   Keywords:  python3.7 pip3.7 pip2.7
      Port:                |
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Comment (by ryandesign):

 Replying to [ticket:59789 duaneellissd]:
 > I am new to Macports, but very familiar with python on linux etc.

 Welcome!

 > I have a new Mac (Catalina) purchased Nov 2019 (with a real Escape key!)

 I'm very jealous :)

 > Then tried to install some packages in the system provided "python3.7"
 via pip.

 I'm not sure if you can install modules into the system- (Apple-)provided
 Python, due to system integrity protection, read-only system volumes and
 so on. And even if it does work (i.e. if they end up getting installed to
 a writable non-system location such as somewhere in /Library) I'm not sure
 if it's a good idea. If you want to install python modules for use
 globally, MacPorts can do that for you; we have thousands of Python
 modules available. (You can search for "py-" on our
 [https://ports.macports.org/ports/category/python/ ports web site].) If a
 module isn't available for what you want, it's usually easy for us (or
 you, with a pull request) to add one.

 On the other hand, if you want to install separate copies of Python
 modules locally into your own Python-based projects (in a "virtual env",
 if I remember the term correctly), then using pip for that is probably
 fine.

 > At the command line if I type:   "pip3.7 install PACKAGE" - I would
 expect to have the package installed in Python 3.7 as provided and came
 with my Mac, or at least the Python3.7 version that comes with MacPorts
 >
 > Instead - it redirects to Python2.7
 >
 > For example:   'pip3.7 install roku' - actually installs the 2.7
 version.
 >
 > 'python3.7 -m pip install roku' works and installs the package into
 Python 3.7
 >
 > Example command output:
 > {{{
 > duane at Duanes-MacBook-Pro ~ % which pip3.7
 > /usr/local/bin/pip3.7
 > }}}

 I don't know where you got this pip3.7, but it wasn't from MacPorts, so I
 can't tell you why it's doing what it's doing. MacPorts installs into
 /opt/local by default, not /usr/local, and having things in /usr/local
 while using MacPorts will cause conflicts and confusion; see
 wiki:FAQ#usrlocal. Perhaps you installed those things with Homebrew, which
 does put things in /usr/local in some circumstances, as far as I know. If
 you would like to continue using MacPorts, then I suggest you remove
 whatever you put in /usr/local before continuing. If you put them there
 with Homebrew, follow their uninstallation instructions.

-- 
Ticket URL: <https://trac.macports.org/ticket/59789#comment:1>
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