File management using openpyxl

When using openpyxl to load workbooks, ensure that your excel file is saved in the same folder as the .py file you are developing.

import openpyxl, pprintprint('Opening workbook... ')wb = openpyxl.load_workbook('censuspopdata.xlsx')sheet = wb.get_sheet_by_name('Population by Census Tract')

Otherwise, the following "file not found" error will result:

 "FileNotFoundError: [Errno 2] No such file or directory: 'censuspopdata.xlsx'"

TypeError: 'generator' object is not subscriptable

Error in chapter 12, which produces the following "TypeError: 'generator' object is not subscriptable" for the code below. 



>>> import openpyxl
>>> wb = openpyxl.load_workbook('example.xlsx')
>>> sheet = wb.active
>>> sheet = wb.active
>>> sheet.columns[1]
Traceback (most recent call last):
  File "<pyshell#4>", line 1, in <module>
    sheet.columns[1]
TypeError: 'generator' object is not subscriptable
>>> 

RESOLUTION: 
Create a list for the sheet.colums: 
list(sheet.columns)[1] to overcome the generator error - outdated method since python 2 apparently. 

More openpyxl learnings

Continuing our journey through Automate the Boring Stuff with Python's excel lessons, we came across the get_column_letter and column_index_from_string openpyxl functions. When attemtping to import the functions, we were given the following error:

 >>> import openpyxl
fr
>>> from openpyxl.cell import get_column_letter, column_index_from_string
Traceback (most recent call last):
  File "<pyshell#8>", line 1, in <module>
    from openpyxl.cell import get_column_letter, column_index_from_string
ImportError: cannot import name 'get_column_letter' from 'openpyxl.cell' (C:\Users\james\AppData\Roaming\Python\Python37\site-packages\openpyxl\cell\__init__.py)
>>> get_column_letter(1)
Traceback (most recent call last):
  File "<pyshell#9>", line 1, in <module>
    get_column_letter(1)
NameError: name 'get_column_letter' is not defined
>>> 
=============================== RESTART: Shell ===============================
>>> import openpyxl
f
>>> 
=============================== RESTART: Shell ===============================
>>> import openpyxl
>>> from openpyxl.cell import get_column_letter
Traceback (most recent call last):
  File "<pyshell#12>", line 1, in <module>
    from openpyxl.cell import get_column_letter
ImportError: cannot import name 'get_column_letter' from 'openpyxl.cell' (C:\Users\james\AppData\Roaming\Python\Python37\site-packages\openpyxl\cell\__init__.py)

Well, apparently the Automate the Boring Stuff with Python is a little out of date now!  According to a StackOverflow contributor,

The function get_column_letter has been relocated in Openpyxl version 2.4 from openpyxl.cell to openpyxl.utils.
The current import is: from openpyxl.utils import get_column_letter

The .utils instead of .cell directory worked. 

Trouble Using Pip and Installing Openpyxl

Openpyxl is, according to Automate the Boring Stuff with Python, supposed to be a handy python library which allows programmers to use python programs with Microsoft excel sheets.

But first you need to install pip on your machine.

What is pip?

"Pip is a package manager for python packages. A package contains all the files you need for a module. Modules are Python code libraries that you can include in your project". - W3 schools. 

The first difficulty I had was getting pip to work through my command line.  I resolved that issue using paths - as described in this video (https://www.youtube.com/watch?v=Jw_MuM2BOuI).

The next issue I had was with installing openpyxl itself (which you need pip to do). I received the following error:

"Could not install packages due to an EnvironmentError: [Errno 13] Permission denied:"

"Consider using the `--user` option or check the permissions" 

Eventually, I found a solution on stackoverflow, which suggested using the following:

python -m pip install --user openpyxl

This worked.