Add python snippet for calculating factorial

snippets/python/math-and-numbers/calculate-compound-interest.md

@@ -2,7 +2,7 @@
 title: Calculate Compound Interest
 description: Calculates compound interest for a given principal amount, rate, and time period.
 author: axorax
-tags: python,math,compound interest,finance
+tags: math,compound interest,finance
 ---
 
 ```py

snippets/python/math-and-numbers/calculate-factorial.md

@@ -0,0 +1,17 @@
+---
+title: Calculate Factiorial of a number
+description: Calculates factorial of a given number using recursive function
+author: SamratBarai
+tags: math,factorial,recursive-function
+---
+
+```py
+def factorial(n):
+    if n < 0: return "Exception: Cannot calculate factorial for negative numbers" # Handling negative number
+    elif n == 0 or n == 1: return 1 # Returns 1 if n is 0 or 1
+    else: return n * factorial(n-1) # Recall the factorial function
+```
+
+# Usage:
+print(factorial(4)) # Returns 24
+print(factorial(-3)) # Returns Exception