title: Resolve Conflicts with Python 2.7 & 3.6 on MacOS Sierra
body: <p>I am just starting to teach myself Python. I'm having trouble getting it set up.</p>
  
  <p>I'm on a MacBook Pro/Sierra. I'm moderately comfortable in command line.</p>
  
  <p>What I'd like to do: run Python 3.6 through Geany. Also, I want to install some libraries (e.g., Requests) and have them work by default in 3.6.</p>
  
  <p>Here's what I've done, in chronological order:</p>
  
  <ol>
  <li>Downloaded/Installed Geany (using dmg package)</li>
  <li>Downloaded/Installed Python 3.6 (from dmg on python.org)</li>
  </ol>
  
  <p>The rest of what I did is in my shell session history below:</p>
  
  <pre><code>Last login: Thu Sep  7 19:52:33 on ttys002
  $ alias python = 'python3.6'
  -bash: alias: python: not found
  -bash: alias: =: not found
  -bash: alias: python3.6: not found
  $ python
  Python 2.7.10 (default, Feb  7 2017, 00:08:15) 
  [GCC 4.2.1 Compatible Apple LLVM 8.0.0 (clang-800.0.34)] on darwin
  Type "help", "copyright", "credits" or "license" for more information.
  &gt;&gt;&gt; ^D
  $ python3
  Python 3.6.2 (v3.6.2:5fd33b5926, Jul 16 2017, 20:11:06) 
  [GCC 4.2.1 (Apple Inc. build 5666) (dot 3)] on darwin
  Type "help", "copyright", "credits" or "license" for more information.
  &gt;&gt;&gt; exit()
  $ alias python = 'python3.6.2'
  -bash: alias: python: not found
  -bash: alias: =: not found
  -bash: alias: python3.6.2: not found
  $ nano .bash_profile
  $ 
    [Restored Sep 7, 2017, 8:16:26 PM]
  Last login: Thu Sep  7 20:16:20 on console
  Restored session: Thu Sep  7 20:08:21 EDT 2017
  $ python -V
  Python 2.7.10
  $ nano .bash_profile
  $ nano ~/.bashrc
  $ source ~/.bashrc
  $ python
  Python 3.6.2 (v3.6.2:5fd33b5926, Jul 16 2017, 20:11:06) 
  [GCC 4.2.1 (Apple Inc. build 5666) (dot 3)] on darwin
  Type "help", "copyright", "credits" or "license" for more information.
  &gt;&gt;&gt; exit()
  $ nano ~/.bash_profile
  $ nano ~/.bashrc
  $ source ~/.bashrc
  $ python
  Python 3.6.2 (v3.6.2:5fd33b5926, Jul 16 2017, 20:11:06) 
  [GCC 4.2.1 (Apple Inc. build 5666) (dot 3)] on darwin
  Type "help", "copyright", "credits" or "license" for more information.
  &gt;&gt;&gt; exit()
  $ brew install python3
  Updating Homebrew...
  ==&gt; Auto-updated Homebrew!
  Updated 2 taps (caskroom/cask, homebrew/core).
  ==&gt; Updated Formulae
  node-build                               vagrant-completion
  
  ==&gt; Installing dependencies for python3: sqlite
  ==&gt; Installing python3 dependency: sqlite
  ==&gt; Downloading https://homebrew.bintray.com/bottles/sqlite-3.20.1.sierra.bottle
  ######################################################################## 100.0%
  ==&gt; Pouring sqlite-3.20.1.sierra.bottle.tar.gz
  ==&gt; Caveats
  This formula is keg-only, which means it was not symlinked into /usr/local,
  because macOS provides an older sqlite3.
  
  If you need to have this software first in your PATH run:
    echo 'export PATH="/usr/local/opt/sqlite/bin:$PATH"' &gt;&gt; ~/.bash_profile
  
  For compilers to find this software you may need to set:
      LDFLAGS:  -L/usr/local/opt/sqlite/lib
      CPPFLAGS: -I/usr/local/opt/sqlite/include
  For pkg-config to find this software you may need to set:
      PKG_CONFIG_PATH: /usr/local/opt/sqlite/lib/pkgconfig
  
  ==&gt; Summary
    /usr/local/Cellar/sqlite/3.20.1: 11 files, 3.0MB
  ==&gt; Installing python3
  ==&gt; Downloading https://homebrew.bintray.com/bottles/python3-3.6.2.sierra.bottle
  ######################################################################## 100.0%
  ==&gt; Pouring python3-3.6.2.sierra.bottle.tar.gz
  Error: The `brew link` step did not complete successfully
  The formula built, but is not symlinked into /usr/local
  Could not symlink bin/2to3-3.6
  Target /usr/local/bin/2to3-3.6
  already exists. You may want to remove it:
    rm '/usr/local/bin/2to3-3.6'
  
  To force the link and overwrite all conflicting files:
    brew link --overwrite python3
  
  To list all files that would be deleted:
    brew link --overwrite --dry-run python3
  
  Possible conflicting files are:
  /usr/local/bin/2to3-3.6 -&gt; /Library/Frameworks/Python.framework/Versions/3.6/bin/2to3-3.6
  /usr/local/bin/idle3 -&gt; /Library/Frameworks/Python.framework/Versions/3.6/bin/idle3
  /usr/local/bin/idle3.6 -&gt; /Library/Frameworks/Python.framework/Versions/3.6/bin/idle3.6
  /usr/local/bin/pydoc3 -&gt; /Library/Frameworks/Python.framework/Versions/3.6/bin/pydoc3
  /usr/local/bin/pydoc3.6 -&gt; /Library/Frameworks/Python.framework/Versions/3.6/bin/pydoc3.6
  /usr/local/bin/python3 -&gt; /Library/Frameworks/Python.framework/Versions/3.6/bin/python3
  /usr/local/bin/python3-config -&gt; /Library/Frameworks/Python.framework/Versions/3.6/bin/python3-config
  /usr/local/bin/python3.6 -&gt; /Library/Frameworks/Python.framework/Versions/3.6/bin/python3.6
  /usr/local/bin/python3.6-config -&gt; /Library/Frameworks/Python.framework/Versions/3.6/bin/python3.6-config
  /usr/local/bin/python3.6m -&gt; /Library/Frameworks/Python.framework/Versions/3.6/bin/python3.6m
  /usr/local/bin/python3.6m-config -&gt; /Library/Frameworks/Python.framework/Versions/3.6/bin/python3.6m-config
  /usr/local/bin/pyvenv -&gt; /Library/Frameworks/Python.framework/Versions/3.6/bin/pyvenv
  /usr/local/bin/pyvenv-3.6 -&gt; /Library/Frameworks/Python.framework/Versions/3.6/bin/pyvenv-3.6
  ==&gt; /usr/local/Cellar/python3/3.6.2/bin/python3 -s setup.py --no-user-cfg instal
  ==&gt; /usr/local/Cellar/python3/3.6.2/bin/python3 -s setup.py --no-user-cfg instal
  ==&gt; /usr/local/Cellar/python3/3.6.2/bin/python3 -s setup.py --no-user-cfg instal
  ==&gt; Caveats
  Pip, setuptools, and wheel have been installed. To update them
    pip3 install --upgrade pip setuptools wheel
  
  You can install Python packages with
    pip3 install &lt;package&gt;
  
  They will install into the site-package directory
    /usr/local/lib/python3.6/site-packages
  
  See: https://docs.brew.sh/Homebrew-and-Python.html
  ==&gt; Summary
    /usr/local/Cellar/python3/3.6.2: 3,598 files, 55.9MB
  $ python --version
  Python 3.6.2
  $ pip --version
  -bash: pip: command not found
  $ pip install -U pip
  -bash: pip: command not found
  $ python get-pip.py
  Requirement already up-to-date: pip in /Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/site-packages
  Collecting wheel
    Downloading wheel-0.29.0-py2.py3-none-any.whl (66kB)
      100% |████████████████████████████████| 71kB 2.2MB/s 
  Installing collected packages: wheel
  Successfully installed wheel-0.29.0
  $ python -V
  Python 3.6.2
  $ pip install -U pip
  -bash: pip: command not found
  $ pip --version
  -bash: pip: command not found
  $ sudo easy_install pip
  Password:
  Searching for pip
  Reading https://pypi.python.org/simple/pip/
  Best match: pip 9.0.1
  Downloading https://pypi.python.org/packages/11/b6/abcb525026a4be042b486df43905d6893fb04f05aac21c32c638e939e447/pip-9.0.1.tar.gz#md5=35f01da33009719497f01a4ba69d63c9
  Processing pip-9.0.1.tar.gz
  Writing /tmp/easy_install-PJCCXY/pip-9.0.1/setup.cfg
  Running pip-9.0.1/setup.py -q bdist_egg --dist-dir /tmp/easy_install-PJCCXY/pip-9.0.1/egg-dist-tmp-MiK6OH
  /System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/distutils/dist.py:267: UserWarning: Unknown distribution option: 'python_requires'
    warnings.warn(msg)
  warning: no previously-included files found matching '.coveragerc'
  warning: no previously-included files found matching '.mailmap'
  warning: no previously-included files found matching '.travis.yml'
  warning: no previously-included files found matching '.landscape.yml'
  warning: no previously-included files found matching 'pip/_vendor/Makefile'
  warning: no previously-included files found matching 'tox.ini'
  warning: no previously-included files found matching 'dev-requirements.txt'
  warning: no previously-included files found matching 'appveyor.yml'
  no previously-included directories found matching '.github'
  no previously-included directories found matching '.travis'
  no previously-included directories found matching 'docs/_build'
  no previously-included directories found matching 'contrib'
  no previously-included directories found matching 'tasks'
  no previously-included directories found matching 'tests'
  creating /Library/Python/2.7/site-packages/pip-9.0.1-py2.7.egg
  Extracting pip-9.0.1-py2.7.egg to /Library/Python/2.7/site-packages
  Adding pip 9.0.1 to easy-install.pth file
  Installing pip script to /usr/local/bin
  Installing pip2.7 script to /usr/local/bin
  Installing pip2 script to /usr/local/bin
  
  Installed /Library/Python/2.7/site-packages/pip-9.0.1-py2.7.egg
  Processing dependencies for pip
  Finished processing dependencies for pip
  $ pip --version
  pip 9.0.1 from /Library/Python/2.7/site-packages/pip-9.0.1-py2.7.egg (python 2.7)
  
  Usage:   
    pip install [options] &lt;requirement specifier&gt; [package-index-options] ...
    pip install [options] -r &lt;requirements file&gt; [package-index-options] ...
    pip install [options] [-e] &lt;vcs project url&gt; ...
    pip install [options] [-e] &lt;local project path&gt; ...
    pip install [options] &lt;archive url/path&gt; ...
  
  $ pip install --user pipenv
  Collecting pipenv
    Downloading pipenv-6.1.4-py2-none-any.whl (665kB)
      100% |████████████████████████████████| 675kB 1.4MB/s 
  Collecting semver (from pipenv)
    Downloading semver-2.7.8.tar.gz
  Collecting setuptools&gt;=36.3.0 (from pipenv)
    Downloading setuptools-36.4.0-py2.py3-none-any.whl (478kB)
      100% |████████████████████████████████| 481kB 1.5MB/s 
  Collecting requests (from pipenv)
    Downloading requests-2.18.4-py2.py3-none-any.whl (88kB)
      100% |████████████████████████████████| 92kB 2.4MB/s 
  Collecting pew&gt;=0.1.26 (from pipenv)
    Downloading pew-0.1.26-py2.py3-none-any.whl
  Collecting virtualenv (from pipenv)
    Downloading virtualenv-15.1.0-py2.py3-none-any.whl (1.8MB)
      100% |████████████████████████████████| 1.8MB 546kB/s 
  Collecting pip-tools&gt;=1.9.0 (from pipenv)
    Downloading pip_tools-1.9.0-py2.py3-none-any.whl
  Requirement already satisfied: pip in /Library/Python/2.7/site-packages/pip-9.0.1-py2.7.egg (from pipenv)
  Collecting idna&lt;2.7,&gt;=2.5 (from requests-&gt;pipenv)
    Downloading idna-2.6-py2.py3-none-any.whl (56kB)
      100% |████████████████████████████████| 61kB 6.3MB/s 
  Collecting urllib3&lt;1.23,&gt;=1.21.1 (from requests-&gt;pipenv)
    Downloading urllib3-1.22-py2.py3-none-any.whl (132kB)
      100% |████████████████████████████████| 133kB 3.2MB/s 
  Collecting certifi&gt;=2017.4.17 (from requests-&gt;pipenv)
    Downloading certifi-2017.7.27.1-py2.py3-none-any.whl (349kB)
      100% |████████████████████████████████| 358kB 1.4MB/s 
  Collecting chardet&lt;3.1.0,&gt;=3.0.2 (from requests-&gt;pipenv)
    Downloading chardet-3.0.4-py2.py3-none-any.whl (133kB)
      100% |████████████████████████████████| 143kB 4.2MB/s 
  Collecting pathlib; python_version == "2.7" (from pew&gt;=0.1.26-&gt;pipenv)
    Downloading pathlib-1.0.1.tar.gz (49kB)
      100% |████████████████████████████████| 51kB 1.9MB/s 
  Collecting backports.shutil-get-terminal-size; python_version == "2.7" (from pew&gt;=0.1.26-&gt;pipenv)
    Downloading backports.shutil_get_terminal_size-1.0.0-py2.py3-none-any.whl
  Collecting shutilwhich; python_version == "2.7" (from pew&gt;=0.1.26-&gt;pipenv)
    Downloading shutilwhich-1.1.0.tar.gz
  Collecting pythonz-bd&gt;=1.10.2 (from pew&gt;=0.1.26-&gt;pipenv)
    Downloading pythonz-bd-1.11.4.tar.gz (86kB)
      100% |████████████████████████████████| 92kB 4.6MB/s 
  Collecting virtualenv-clone&gt;=0.2.5 (from pew&gt;=0.1.26-&gt;pipenv)
    Downloading virtualenv-clone-0.2.6.tar.gz
  Requirement already satisfied: six in /System/Library/Frameworks/Python.framework/Versions/2.7/Extras/lib/python (from pip-tools&gt;=1.9.0-&gt;pipenv)
  Collecting click&gt;=6 (from pip-tools&gt;=1.9.0-&gt;pipenv)
    Downloading click-6.7-py2.py3-none-any.whl (71kB)
      100% |████████████████████████████████| 71kB 2.8MB/s 
  Collecting first (from pip-tools&gt;=1.9.0-&gt;pipenv)
    Downloading first-2.0.1-py2.py3-none-any.whl
  Installing collected packages: semver, setuptools, idna, urllib3, certifi, chardet, requests, pathlib, backports.shutil-get-terminal-size, virtualenv, shutilwhich, pythonz-bd, virtualenv-clone, pew, click, first, pip-tools, pipenv
    Running setup.py install for semver ... done
    Running setup.py install for pathlib ... done
    Running setup.py install for shutilwhich ... done
    Running setup.py install for pythonz-bd ... done
    Running setup.py install for virtualenv-clone ... done
  Successfully installed backports.shutil-get-terminal-size-1.0.0 certifi-2017.7.27.1 chardet-3.0.4 click-6.7 first-2.0.1 idna-2.6 pathlib-1.0.1 pew-0.1.26 pip-tools-1.9.0 pipenv-6.1.4 pythonz-bd-1.11.4 requests-2.18.4 semver-2.7.8 setuptools-36.4.0 shutilwhich-1.1.0 urllib3-1.22 virtualenv-15.1.0 virtualenv-clone-0.2.6
  $ cd Project
  Project steve$ pipenv install requests
  -bash: pipenv: command not found
  Project steve$ pip install --user pipenv
  Requirement already satisfied: pipenv in /Users/steve/Library/Python/2.7/lib/python/site-packages
  Requirement already satisfied: semver in /Users/steve/Library/Python/2.7/lib/python/site-packages (from pipenv)
  Requirement already satisfied: setuptools&gt;=36.3.0 in /Users/steve/Library/Python/2.7/lib/python/site-packages (from pipenv)
  Requirement already satisfied: requests in /Users/steve/Library/Python/2.7/lib/python/site-packages (from pipenv)
  Requirement already satisfied: pew&gt;=0.1.26 in /Users/steve/Library/Python/2.7/lib/python/site-packages (from pipenv)
  Requirement already satisfied: virtualenv in /Users/steve/Library/Python/2.7/lib/python/site-packages (from pipenv)
  Requirement already satisfied: pip-tools&gt;=1.9.0 in /Users/steve/Library/Python/2.7/lib/python/site-packages (from pipenv)
  Requirement already satisfied: pip in /Library/Python/2.7/site-packages/pip-9.0.1-py2.7.egg (from pipenv)
  Requirement already satisfied: idna&lt;2.7,&gt;=2.5 in /Users/steve/Library/Python/2.7/lib/python/site-packages (from requests-&gt;pipenv)
  Requirement already satisfied: urllib3&lt;1.23,&gt;=1.21.1 in /Users/steve/Library/Python/2.7/lib/python/site-packages (from requests-&gt;pipenv)
  Requirement already satisfied: certifi&gt;=2017.4.17 in /Users/steve/Library/Python/2.7/lib/python/site-packages (from requests-&gt;pipenv)
  Requirement already satisfied: chardet&lt;3.1.0,&gt;=3.0.2 in /Users/steve/Library/Python/2.7/lib/python/site-packages (from requests-&gt;pipenv)
  Requirement already satisfied: pathlib; python_version == "2.7" in /Users/steve/Library/Python/2.7/lib/python/site-packages (from pew&gt;=0.1.26-&gt;pipenv)
  Requirement already satisfied: backports.shutil-get-terminal-size; python_version == "2.7" in /Users/steve/Library/Python/2.7/lib/python/site-packages (from pew&gt;=0.1.26-&gt;pipenv)
  Requirement already satisfied: shutilwhich; python_version == "2.7" in /Users/steve/Library/Python/2.7/lib/python/site-packages (from pew&gt;=0.1.26-&gt;pipenv)
  Requirement already satisfied: pythonz-bd&gt;=1.10.2 in /Users/steve/Library/Python/2.7/lib/python/site-packages (from pew&gt;=0.1.26-&gt;pipenv)
  Requirement already satisfied: virtualenv-clone&gt;=0.2.5 in /Users/steve/Library/Python/2.7/lib/python/site-packages (from pew&gt;=0.1.26-&gt;pipenv)
  Requirement already satisfied: six in /System/Library/Frameworks/Python.framework/Versions/2.7/Extras/lib/python (from pip-tools&gt;=1.9.0-&gt;pipenv)
  Requirement already satisfied: click&gt;=6 in /Users/steve/Library/Python/2.7/lib/python/site-packages (from pip-tools&gt;=1.9.0-&gt;pipenv)
  Requirement already satisfied: first in /Users/steve/Library/Python/2.7/lib/python/site-packages (from pip-tools&gt;=1.9.0-&gt;pipenv)
  Project steve$ pipenv install requests
  -bash: pipenv: command not found
  Project steve$ python3.6 -m pipenv install
  /Library/Frameworks/Python.framework/Versions/3.6/bin/python3.6: No module named pipenv
  Project steve$ python3.6 -m pip install
  You must give at least one requirement to install (see "pip help install")
  Project steve$ brew install intltool
  Updating Homebrew...
  ==&gt; Auto-updated Homebrew!
  Updated 1 tap (caskroom/cask).
  No changes to formulae.
  
  ==&gt; Downloading https://homebrew.bintray.com/bottles/intltool-0.51.0.sierra.bott
  ######################################################################## 100.0%
  ==&gt; Pouring intltool-0.51.0.sierra.bottle.tar.gz
    /usr/local/Cellar/intltool/0.51.0: 19 files, 185.9KB
  Project steve$ python
  Python 3.6.2 (v3.6.2:5fd33b5926, Jul 16 2017, 20:11:06) 
  [GCC 4.2.1 (Apple Inc. build 5666) (dot 3)] on darwin
  Type "help", "copyright", "credits" or "license" for more information.
  &gt;&gt;&gt; exit()
  Project steve$ pipenv --three
  -bash: pipenv: command not found
  Project steve$ python3.6 -m pipenv install
  /Library/Frameworks/Python.framework/Versions/3.6/bin/python3.6: No module named pipenv
  Project steve$ 
  $ brew link --overwrite --dry-run python3
  Would remove:
  /usr/local/bin/2to3-3.6 -&gt; /Library/Frameworks/Python.framework/Versions/3.6/bin/2to3-3.6
  /usr/local/bin/idle3 -&gt; /Library/Frameworks/Python.framework/Versions/3.6/bin/idle3
  /usr/local/bin/idle3.6 -&gt; /Library/Frameworks/Python.framework/Versions/3.6/bin/idle3.6
  /usr/local/bin/pydoc3 -&gt; /Library/Frameworks/Python.framework/Versions/3.6/bin/pydoc3
  /usr/local/bin/pydoc3.6 -&gt; /Library/Frameworks/Python.framework/Versions/3.6/bin/pydoc3.6
  /usr/local/bin/python3 -&gt; /Library/Frameworks/Python.framework/Versions/3.6/bin/python3
  /usr/local/bin/python3-config -&gt; /Library/Frameworks/Python.framework/Versions/3.6/bin/python3-config
  /usr/local/bin/python3.6 -&gt; /Library/Frameworks/Python.framework/Versions/3.6/bin/python3.6
  /usr/local/bin/python3.6-config -&gt; /Library/Frameworks/Python.framework/Versions/3.6/bin/python3.6-config
  /usr/local/bin/python3.6m -&gt; /Library/Frameworks/Python.framework/Versions/3.6/bin/python3.6m
  /usr/local/bin/python3.6m-config -&gt; /Library/Frameworks/Python.framework/Versions/3.6/bin/python3.6m-config
  /usr/local/bin/pyvenv -&gt; /Library/Frameworks/Python.framework/Versions/3.6/bin/pyvenv
  /usr/local/bin/pyvenv-3.6 -&gt; /Library/Frameworks/Python.framework/Versions/3.6/bin/pyvenv-3.6
  $ brew link --overwrite python3
  Linking /usr/local/Cellar/python3/3.6.2... 19 symlinks created
  $ rm '/usr/local/bin/2to3-3.6'
  $ brew link --overwrite python3
  Warning: Already linked: /usr/local/Cellar/python3/3.6.2
  To relink: brew unlink python3 &amp;&amp; brew link python3
  $ brew unlink python3 &amp;&amp; brew link python3
  Unlinking /usr/local/Cellar/python3/3.6.2... 22 symlinks removed
  Linking /usr/local/Cellar/python3/3.6.2... 23 symlinks created
  $ pip3 install --upgrade pip setuptools wheel
  Requirement already up-to-date: pip in /Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/site-packages
  Collecting setuptools
    Using cached setuptools-36.4.0-py2.py3-none-any.whl
  Requirement already up-to-date: wheel in /Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/site-packages
  Installing collected packages: setuptools
    Found existing installation: setuptools 28.8.0
      Uninstalling setuptools-28.8.0:
        Successfully uninstalled setuptools-28.8.0
  Successfully installed setuptools-36.4.0
  $ python --version
  Python 2.7.10
  $ 
  </code></pre>
  
  <p>I'm a complete newbie in Python, and not a professional programmer. I researched this all afternoon yesterday.</p>
  
  <p>Thanks for any help!</p>