如何在Views.py中运行函数并打印结果？ — Django

Question

The problem is that I am trying to call a function from my views.py and print the result in my template through a context variable. The function prints in the terminal and does not work in the template. I posted a question a few days ago regarding doing this with subprocess, but I still could not figure it out.

How can I print "This is a test function for AAPL" in my template instead of in the terminal?

Views.py

from django.shortcuts import render  
from backtests.scripts import Backtests

def index(request):

    if 'symbol' in request.GET:
        symbol = request.GET.get('symbol','Invalid Symbol')
        request.session['symbol'] = symbol
    else:
        symbol = request.session['symbol']


    earnings_object = Backtests("AAPL")
    test = earnings_object.print_discrep()


    return render(request, 'backtests/earnings.html', {'symbol':symbol, 'test':test})

scripts.py

class Backtests:

    def __init__(self, symbol):
        self.symbol = symbol

    def print_discrep(self):
        print('This is a test function for the graph ' + self.symbol)

It is returning None in my template.

Answer 1

You're calling the function in the view. To call it in the template, assign the function object, not the result of the function call:

test = earnings_object.print_discrep  # no ()

Update: print prints to the command line, not into your template.

The template displays the return value of functions you call. Your print_discrep doesn't have a return value, defaulting to None .

If you want to display data in the template, return that data in your function:

def get_discrep(self):
    return 'This is a test function for the graph ' + self.symbol

Then you can call the function either in the view or in the template.