diff --git a/data_structures/binary_tree/binary_search_tree.py b/data_structures/binary_tree/binary_search_tree.py
index 46c5ccca032c..86dcd6489bd5 100644
--- a/data_structures/binary_tree/binary_search_tree.py
+++ b/data_structures/binary_tree/binary_search_tree.py
@@ -56,13 +56,13 @@ def __insert(self, value):
             parent_node = self.root  # from root
             while True:  # While we don't get to a leaf
                 if value < parent_node.value:  # We go left
-                    if parent_node.left == None:
+                    if parent_node.left is None:
                         parent_node.left = new_node  # We insert the new node in a leaf
                         break
                     else:
                         parent_node = parent_node.left
                 else:
-                    if parent_node.right == None:
+                    if parent_node.right is None:
                         parent_node.right = new_node
                         break
                     else:
diff --git a/dynamic_programming/optimal_binary_search_tree.py b/dynamic_programming/optimal_binary_search_tree.py
index b0f248acf35c..f33ca01bd933 100644
--- a/dynamic_programming/optimal_binary_search_tree.py
+++ b/dynamic_programming/optimal_binary_search_tree.py
@@ -24,6 +24,7 @@
 
 class Node:
     """Binary Search Tree Node"""
+
     def __init__(self, key, freq):
         self.key = key
         self.freq = freq
diff --git a/hashes/hamming_code.py b/hashes/hamming_code.py
index aae39ed9a06f..756ba7c6670f 100644
--- a/hashes/hamming_code.py
+++ b/hashes/hamming_code.py
@@ -140,7 +140,7 @@ def emitterConverter(sizePar, data):
     # Mount the message
     ContBP = 0  # parity bit counter
     for x in range(0, sizePar + len(data)):
-        if dataOrd[x] == None:
+        if dataOrd[x] is None:
             dataOut.append(str(parity[ContBP]))
             ContBP += 1
         else:
@@ -243,7 +243,7 @@ def receptorConverter(sizePar, data):
     # Mount the message
     ContBP = 0  # Parity bit counter
     for x in range(0, sizePar + len(dataOutput)):
-        if dataOrd[x] == None:
+        if dataOrd[x] is None:
             dataOut.append(str(parity[ContBP]))
             ContBP += 1
         else:
diff --git a/maths/bisection.py b/maths/bisection.py
index a9df15b775b3..93cc2247b64e 100644
--- a/maths/bisection.py
+++ b/maths/bisection.py
@@ -6,6 +6,8 @@
 
 https://en.wikipedia.org/wiki/Bisection_method
 """
+
+
 def equation(x: float) -> float:
     """
     >>> equation(5)
diff --git a/searches/tabu_search.py b/searches/tabu_search.py
index 04a0e5076912..2847dca7acd7 100644
--- a/searches/tabu_search.py
+++ b/searches/tabu_search.py
@@ -25,7 +25,6 @@
 
 import copy
 import argparse
-import sys
 
 
 def generate_neighbours(path):
@@ -278,4 +277,4 @@ def main(args=None):
     )
 
     # Pass the arguments to main method
-    sys.exit(main(parser.parse_args()))
+    main(parser.parse_args())
diff --git a/strings/aho-corasick.py b/strings/aho-corasick.py
index 315f7793325e..bb6955bdd423 100644
--- a/strings/aho-corasick.py
+++ b/strings/aho-corasick.py
@@ -47,7 +47,7 @@ def set_fail_transitions(self):
                 q.append(child)
                 state = self.adlist[r]["fail_state"]
                 while (
-                    self.find_next_state(state, self.adlist[child]["value"]) == None
+                    self.find_next_state(state, self.adlist[child]["value"]) is None
                     and state != 0
                 ):
                     state = self.adlist[state]["fail_state"]