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Python Flask Basics Welcome to Flask Multiply View

Posted by hualnermorales
hualnermorales
736 Points

Task 5 of 5: Multiply 5*5. I have clearly defined num1 but continue to get an error...

"Bummer: NameError: name 'num1' is not defined"

flask_app.py 
from flask import Flask

app = Flask(__name__)

@app.route('/multiply')
@app.route('/multiply/<int:num1>/<int:num2>')
@app.route('/multiply/<float:num1>/<int:num2>')
@app.route('/multiply/<int:num1>/<float:num2>')
@app.route('/multiply/<float:num1>/<float:num2>')
def multiply(num1=5,num2=5,product=num1*num2):
    return '{} * {} = {}'.format(num1, num2, product)

3 Answers

hualnermorales
hualnermorales
736 Points

Got the correct answer:

def multiply(num1 = 5, num2 = 5):
    product = num1 * num2
    return '{}'.format(product)
Anthony Crespo
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Anthony Crespo
Python Web Development Techdegree Student 12,961 Points
Anthony Crespo
.a{fill-rule:evenodd;}techdegree
Anthony Crespo
Python Web Development Techdegree Student 12,961 Points

Oh yeah you right! It has to return only the product and not the whole mathematical formula. Sorry lol I corrected your code but didn't read the challenge.

You can even drop the product variable and make it shorter.

def multiply(num1 = 5, num2 = 5):
    return f'{num1 * num2}'
hualnermorales
hualnermorales
736 Points

Anthony, thats pretty cool.

The lone 'f' allows you to perform a mathematical formula within the curly brackets I presume? 

return f'{num1 * num2}'
Anthony Crespo
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.a{fill-rule:evenodd;}techdegree
Anthony Crespo
Python Web Development Techdegree Student 12,961 Points
Anthony Crespo
.a{fill-rule:evenodd;}techdegree
Anthony Crespo
Python Web Development Techdegree Student 12,961 Points

It's the new fstring (Python 3.6). It work the same as .format() but it's way shorter.

num1 = 5
num2 = 5
string = f'{num1} + {num2} = {num1 * num2}'
Anthony Crespo
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.a{fill-rule:evenodd;}techdegree
Anthony Crespo
Python Web Development Techdegree Student 12,961 Points
Anthony Crespo
.a{fill-rule:evenodd;}techdegree
Anthony Crespo
Python Web Development Techdegree Student 12,961 Points

I don't think you can multiply local variable in there. (Maybe, I just don't know how?) If it's inside the function it works:

def multiply(num1=5,num2=5):
    product = num1 * num2
    return '{} * {} = {}'.format(num1, num2, product)

The way I understand it's that the arguments don't exist outside the scope of the body of the function cause if you use global variables it works:

a = 5
b = 5
def multiply(num1=5,num2=5, product = a * a):
    return '{} * {} = {}'.format(num1, num2, product)
hualnermorales
hualnermorales
736 Points
hualnermorales
hualnermorales
736 Points

Hey Anthony C., I think the question may be looking for something else because I'm still getting error messages...

'Bummer: Didn't get the expected response. Got 5 * 5 = 25.'

The quiz is telling us here that it doesn't want '5 * 5 = 25' as an answer. What solution could it be looking for?

def multiply(num1 = 5, num2 = 5):
    product = num1 * num2
    return '{} * {} = {}'.format(num1, num2, product)