(i) Python stops calling recursive function after 1000 calls by default. 
(ii) So, it also allows you to change the limit using sys.setrecursionlimit (limit_value).
Example:
import sys
sys.setrecursionlimit(3000)
def fact(n):
         if n == 0:
         return 1
         else:
         return n * fact(n-1)
print(fact (2000))

(i)  A recursive function calls itself.
(ii) The condition that is applied in any recursive function is known as base condition.
(iii)  A base condition is must in every recursive function otherwise it will continue to execute like an infinite loop.

A variable with global scope can be used anywhere in the program. It can be created by defining a variable outside the scope of any function.

Scope of variable refers to the part of the program, where it is accessible, i.e., area where the variables can refer (use) it. The scope holds the current set of variables and their values. The two types of scopes - local scope and global scope.

Main advantages of functions are
(i) It avoids repetition and makes a high degree of code reusing.
(ii) It provides better modularity for your application.

(i) User defined functions.
(ii) Built in functions.
(iii) Lambda functions.
(iv) Recursion functions.

(i) Functions are named blocks of code that are designed to do specific job.
(ii) If you need to perform that task multiple times throughout your program, you just call the function dedicated to handling that task.