Getting error while trying to run this command ” pipenv install requests ” in mac OS

I am facing the following error:

Warning: the environment variable LANG is not set!
We recommend setting this in ~/.profile (or equivalent) for proper expected behavior.
Creating a virtualenv for this project…
Using /usr/local/opt/python/bin/python3.6 (3.6.4) to create virtualenv…
⠋Traceback (most recent call last):
  File "/usr/local/Cellar/python/3.6.4_4/Frameworks/Python.framework/Versions/3.6/lib/python3.6/runpy.py", line 193, in _run_module_as_main
    "__main__", mod_spec)
  File "/usr/local/Cellar/python/3.6.4_4/Frameworks/Python.framework/Versions/3.6/lib/python3.6/runpy.py", line 85, in _run_code
    exec(code, run_globals)
  File "/usr/local/lib/python3.6/site-packages/pipenv/pew/__main__.py", line 8, in <module>
    import pew
  File "/usr/local/lib/python3.6/site-packages/pipenv/patched/pew/__init__.py", line 1, in <module>
    from . import pew
  File "/usr/local/lib/python3.6/site-packages/pipenv/patched/pew/pew.py", line 41, in <module>
    from pew._utils import (check_call, invoke, expandpath, own, env_bin_dir,
  File "/usr/local/lib/python3.6/site-packages/pipenv/patched/pew/_utils.py", line 22, in <module>
    encoding = locale.getlocale()[1] or 'ascii'
  File "/usr/local/Cellar/python/3.6.4_4/Frameworks/Python.framework/Versions/3.6/lib/python3.6/locale.py", line 581, in getlocale
    return _parse_localename(localename)
  File "/usr/local/Cellar/python/3.6.4_4/Frameworks/Python.framework/Versions/3.6/lib/python3.6/locale.py", line 490, in _parse_localename
    raise ValueError('unknown locale: %s' % localename)
ValueError: unknown locale: UTF-8

Virtualenv location:

Creating a Pipfile for this project…
Traceback (most recent call last):
  File "/usr/local/bin/pipenv", line 11, in <module>
    sys.exit(cli())
  File "/usr/local/lib/python3.6/site-packages/pipenv/vendor/click/core.py", line 722, in __call__
    return self.main(*args, **kwargs)
  File "/usr/local/lib/python3.6/site-packages/pipenv/vendor/click/core.py", line 697, in main
    rv = self.invoke(ctx)
  File "/usr/local/lib/python3.6/site-packages/pipenv/vendor/click/core.py", line 1066, in invoke
    return _process_result(sub_ctx.command.invoke(sub_ctx))
  File "/usr/local/lib/python3.6/site-packages/pipenv/vendor/click/core.py", line 895, in invoke
    return ctx.invoke(self.callback, **ctx.params)
  File "/usr/local/lib/python3.6/site-packages/pipenv/vendor/click/core.py", line 535, in invoke
    return callback(*args, **kwargs)
  File "/usr/local/lib/python3.6/site-packages/pipenv/cli.py", line 366, in install
    selective_upgrade=selective_upgrade,
  File "/usr/local/lib/python3.6/site-packages/pipenv/core.py", line 1761, in do_install
    skip_requirements=skip_requirements,
  File "/usr/local/lib/python3.6/site-packages/pipenv/core.py", line 636, in ensure_project
    ensure_pipfile(validate=validate, skip_requirements=skip_requirements)
  File "/usr/local/lib/python3.6/site-packages/pipenv/core.py", line 289, in ensure_pipfile
    project.create_pipfile(python=python)
  File "/usr/local/lib/python3.6/site-packages/pipenv/project.py", line 518, in create_pipfile
    'python_version': python_version(required_python)[: len('2.7')]
TypeError: 'NoneType' object is not subscriptable

I tried setting the LANG in ~/.profile and ~/.bash_profile. Both didn’t work.

Answer

What worked for me on Mac OS X Sierra is adding the following into my ~/.bash_profile file:

export LANG="en_US.UTF-8"
export LC_ALL="en_US.UTF-8"
export LC_CTYPE="en_US.UTF-8"

Then I reloaded the bash profile with: source ~/.bash_profile

For those who use zsh shell, you must add those lines to your ~/.zshrc

export LANG="en_US.UTF-8"
export LC_ALL="en_US.UTF-8"
export LC_CTYPE="en_US.UTF-8"

Then I reload the bash profile with: source ~/.zshrc