Python: How do I return to a variable within a function?

Question

For a starter project, I am trying to write a piece of code that will open a GUI that can be used to select a PDF filepath that is then read and saved to a variable. Currently I am returning the results of a function and then trying to print the function. This must not be what I really want to do because when I print the function I am essentially running it again instead of just printing the returned string. Would the best solution be to save returned string to a variable within the function and then call that into the print statement later on?

I admittedly lack a basic understanding of what I am doing and nearly all of my code is frankensteined from fifty other posts made by other people. I'm sorry in advance for spamming the boards with a low level question like this, but I've been having trouble creating a search that finds an answer that I understand. Here is my code currently....

import PyPDF2
import tkinter
    
from tkinter import filedialog
    
root = tkinter.Tk()
root.withdraw()
    
def key_search():
    filename = filedialog.askopenfilename(parent=root, title='Choose File Path')  # Credit: https://stackoverflow.com/questions/3643418/storing-file-path-using-windows-explorer-browser-in-python
    with open(filename, mode='rb') as f: #rb = read only binary, 'f' is a custom file object. Credit: https://www.soudegesu.com/en/post/python/extract-text-from-pdf-with-pypdf2/
        reader = PyPDF2.PdfFileReader(f)
        for page in reader.pages:
            return(page.extractText())
    
print(key_search())

Sorry, it is not really clear what you are trying to do, nor in how far what you have doesn't do that. It might help to build a [mcve] that does *not* rely on PDFs and GUIs to run – your description implies a simple function reading e.g. ``time.time()`` might be enough. At any rate, consider to do the [Python tutorial](https://docs.python.org/3/tutorial/index.html) to get familiar with the terms used to describe code. — MisterMiyagi, Feb 07 '21 at 19:38

score 1 · Accepted Answer · answered Feb 07 '21 at 19:34

1

There are two things to improve here, first, if you want to save the result of a function you can just save it to a variable like this

result = key_search()
print(result)

The second, notice that when you return from a function, it quits the function in that moment. Let's say that reader.pages has 5 pages, your function currently reads the first one and quits. If you want to read all of them you first need to save the results to a list then return the list

results = []
for page in reader.pages:
    results.append(page.extractText())
return results # Notice you dont need parentheses here

Then you can print all the results

pages = key_search()
for page in pages:
    print(page)

There are more standard/efficient ways to do those things, but since you are just beginning it's better to see things clearer like that

answered Feb 07 '21 at 19:34

Ron Serruya

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Thank you! I actually have another, general, question. In the context of this code what is "page" ? I never created a variable called "page" so I don't know what it is related to or how my code recognizes what it is. – Sean Kennedy Feb 07 '21 at 20:15
This is pretty basic so I'm sure you will find better explanations if you just search for `for loops in python`. But in short `pages` is iterable, which means you can iterate through it. So in this case you are telling the code to go through the list of `pages`, and for each item in the list assign it to a variable called `page`. Most other languages call it `foreach`. https://realpython.com/python-for-loop/#the-python-for-loop – Ron Serruya Feb 07 '21 at 23:02

Python: How do I return to a variable within a function?

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