Add recursive factorial function in question.py

Implement recursive function to calculate factorial.

Author: codewithdhruba01

12_Recursion/question.py

@@ -0,0 +1,10 @@
+## Factorial of a number nikalne ke liye recursive function likho. 
+
+def factorial(n):
+    if n == 0 or n == 1:
+        return 1
+    return n * factorial(n - 1)
+
+print(factorial(5))  # Output: 120
+
+## Har step me number ko uske previous number ke factorial se multiply karte hain.