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Python Flask Basics Welcome to Flask Request Variables

Posted by vikas pal
vikas pal
11,563 Points

what is global?

please tell me in brief what is global in thus video.i also doesn't understand it from teachers notes.please tell me what it is.

vikas pal
vikas pal
11,563 Points

Kenneth Love Ken Alger

1 Answer

Alexander Davison
Alexander Davison
65,469 Points

If you define variables in the global scope (a variable is in the global scope if you don't define it in functions), it is accessable anywhere in your program:

# Not in any kind of function
name = "Alex"

If you define a variable in the function scope (when you define it inside a function), that variable is only accessable to that function:

>>> # in the Python Shell
>>>
>>> def some_func():
...        name = "Alex"
...        print(name)

>>> some_func()
Alex
>>> name
Traceback (most recent call last):
    File <pyshell#3>, line 1, in <module>
        name
NameError: name 'name' is not defined

But, it is possible to make it go the global scope, too:

def some_func():
    global name
    name = "Alex"

However, it's considered bad practices in many ways, so try not to use it too often :)

It can make your program more confusing.

Good luck! I hope you understand! ~Alex