Trouble Installing with Pip Command

Created originally on Bitbucket by AlexLCheungy (Alexander Cheung)

on macOS using pip install openpyxl

Traceback (most recent call last): File "test.py", line 1, in from openpyxl import load_workbook File "/usr/local/lib/python2.7/site-packages/openpyxl/init.py", line 29, in from openpyxl.workbook import Workbook File "/usr/local/lib/python2.7/site-packages/openpyxl/workbook/init.py", line 5, in from .workbook import Workbook File "/usr/local/lib/python2.7/site-packages/openpyxl/workbook/workbook.py", line 7, in from openpyxl.worksheet import Worksheet File "/usr/local/lib/python2.7/site-packages/openpyxl/worksheet/init.py", line 4, in from .worksheet import Worksheet File "/usr/local/lib/python2.7/site-packages/openpyxl/worksheet/worksheet.py", line 35, in from openpyxl.cell import Cell File "/usr/local/lib/python2.7/site-packages/openpyxl/cell/init.py", line 4, in from .cell import Cell, WriteOnlyCell File "/usr/local/lib/python2.7/site-packages/openpyxl/cell/cell.py", line 15, in from copy import copy File "/usr/local/Cellar/python@2/2.7.14_3/Frameworks/Python.framework/Versions/2.7/lib/python2.7/copy.py", line 52, in import weakref File "/usr/local/Cellar/python@2/2.7.14_3/Frameworks/Python.framework/Versions/2.7/lib/python2.7/weakref.py", line 14, in from _weakref import ( ImportError: cannot import name _remove_dead_weakref