Adopt `python -m pip install --upgrade pip` to upgrade pip

[sumedhbala]

Hit this on a Mac running High Sierra, Version .10.13.6 (17G65)
"""
default: Downloading https://files.pythonhosted.org/packages/5f/25/e52d3f31441505a5f3af41213346e5b6c221c9e086a166f3703d2ddaf940/pip-18.0-py2.py3-none-any.whl (1.3MB)
default: Installing collected packages: pip
default: Found existing installation: pip 8.1.1
default: Not uninstalling pip at /usr/lib/python2.7/dist-packages, outside environment /usr
default: Successfully installed pip-18.0
default: Traceback (most recent call last):
default: File "/usr/bin/pip", line 9, in
default:
default: from pip import main
default: ImportError
default: :
default: cannot import name main
default: Traceback (most recent call last):
default: File "/usr/bin/pip", line 9, in
default:
default: from pip import main
default: ImportError
default: :
default: cannot import name main
default: Traceback (most recent call last):
default: File "/usr/bin/pip", line 9, in
default:
default: from pip import main
default: ImportError
default: :
default: cannot import name main
default: Traceback (most recent call last):
default: File "/usr/bin/pip", line 9, in
default:
default: from pip import main
default: ImportError
default: :
default: cannot import name main
default: Traceback (most recent call last):
default: File "/usr/bin/pip", line 9, in
default:
default: from pip import main
default: ImportError
default: :
default: cannot import name main
default: Traceback (most recent call last):
default: File "/usr/bin/pip", line 9, in
default:
default: from pip import main
default: ImportError
default: :
default: cannot import name main
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went wrong.
"""

s/pip install --upgrade pip/python -m pip install --upgrade pip/ in pg_config.sh seems to make it work for me.
Also Reading posts like https://stackoverflow.com/questions/25749621/whats-the-difference-between-pip-install-and-python-m-pip-install tell you to use python -m pip to install/update packages

[out-running-27]

Thanks changing:
pip install --upgrade pip -> python -m pip install --upgrade pip
seemed to work for me as well

[javenschuetz]

Thanks for posting, it worked.