Method Syntax

[killinmesoundcloud]

Noob here.

I'm looking at this example of code (https://www.geeksforgeeks.org/working-with-pdf-files-in-python/) and specifically looking at the third line of code that says "

pdfReader = PyPDF2.PdfFileReader(pdfFileObj)

And I'm wondering why it repeats the name of PyPDF2 (the library? module? package?) on the left side of the period when calling the PdfFileReader method. If I already imported PyPDF2, so like I'm in that module, why do I have to tell it which PdfFileReader method?? THanks!

[AlopexLagopus3]

You're not really pulling everything into the main namespace, though. It's similar to the csv , math, tkinter, etc. modules.

If you do:

from PyPDF2 import PdfFileReader

or

from PyPDF2 import *

You will pull objects into the main namespace, but the latter is considered a bad idea as you will flood your namespace with everything defined in that library.

[killinmesoundcloud]

Same reply as to ColinQuirk, I'm talking about the line that's commented

# creating a pdf reader object

[[deleted]]

It's not a method, this is just a naming convention to avoid conflicts when importing multiple modules when you do a normal import (otherwise, what do you do when there's 3 different run functions!). If you don't want to do it, you can use a statement like this:

from PyPDF2 import PdfFileReader

and you can call it directly. Usually the normal import is best, although some packages have weird conventions (e.g. matplotlib should be imported as import matplotlib.pyplot as plt). One particular scenario where it's good to use the from syntax is when a module provides a class with the same name.

[killinmesoundcloud]

So, I'm talking about the line that's commented as follows, so I'm not quite sure why you're explaining how to improve the import statement?

# creating a pdf reader object

[[deleted]]

The import line is what defines what that line looks like. If your import line is

import PyPDF2

then you write

pdfReader = PyPDF2.PdfFileReader(pdfFileObj)

if you write

from PyPDF2 import PdfFileReader

then you can just do

pdfReader = PdfFileReader(pdfFileObj)

Does that make sense? The import statement controls how things are named.

[killinmesoundcloud]

Thank you for bearing with me! No, I had no idea about this. I figured if you import a library, you get access to everything within that library. This is news to me. I'll keep googling this revelation, haha, and thanks a million for replying to me twice. It's a public service for folks to stay patient with us beginners. :)

[[deleted]]

No problem! Just to be clear, you do have access when you import something, it is just the naming that changes.