complete parts 1 and 2

part-1.py

@@ -4,17 +4,35 @@
 # the appropriate comment.
 
 # factorial
-
+def factorial(n):
+    if n < 0:
+        raise ValueError("Only positive numbers")
+    if n == 0:
+        return 1
+    return n * factorial(n - 1)
 
 
 # reverse
-
+def reverse(text):
+    if len(text) <= 1:
+        return text
+    return reverse(text[1:]) + text[0]
 
 
 # bunny
-
+def bunny(count):
+    if count == 0:
+        return 0
+    return bunny(count - 1) + 2
 
 
 # is_nested_parens
-
+def is_nested_parens(parens):
+    if parens == "":
+        return True
+    if len(parens) % 2 != 0:
+        return False
+    if parens[0] == "(" and parens[-1] == ")":
+        return is_nested_parens(parens[1:-1])
+    return False
 

part-2.py

@@ -4,13 +4,41 @@
 # the appropriate comment.
 
 # search
-
+def search(array, query):
+    if not array:
+        return False
+    if array[0] == query:
+        return True
+    return search(array[1:], query)
 
 
 # is_palindrome
-
+def is_palindrome(text):
+    if len(text) <= 1:
+        return True
+    if text[0] != text[-1]:
+        return False
+
+    return is_palindrome(text[1:-1])
 
 
 # digit_match
+def digit_match(num1, num2):
+    if num1 < 0 or num2 < 0:
+        raise ValueError("Numbers must be non-negative")
+
+    if num1 == 0 and num2 == 0:
+        return 1
+
+    elif num1 < 10 or num2 < 10:
+        if num1 % 10 == num2 % 10:
+            return 1
+        return 0
+
+    if num1 % 10 == num2 % 10:
+        return 1 + digit_match(num1 // 10, num2 // 10)
+
+    return digit_match(num1 // 10, num2 // 10)
+