diff --git a/error.py b/error.py
index f86feef..7d0dba7 100644
--- a/error.py
+++ b/error.py
@@ -1,4 +1,4 @@
-#! python
+#!/usr/bin/env python
 import json
 
 with open('./output/students.json') as f: students = json.load(f)
diff --git a/scheduleGenerator/generator.py b/scheduleGenerator/generator.py
index c214279..56b3ba3 100644
--- a/scheduleGenerator/generator.py
+++ b/scheduleGenerator/generator.py
@@ -1,4 +1,4 @@
-#! python
+#!/usr/bin/env python
 import json
 import random
 from inspect import currentframe
@@ -266,10 +266,10 @@ def generateScheduleV3(
   # Step 4 - Attempt to fit classes into timetable
   def stepIndex(offset: int, stepType: int) -> int:
     # stepType 0 is for stepping between first and second semester
-    if stepType == 0: return 5 if offset == 0 or offset == -4 else -4
+    if stepType == 0: return 5 if offset in (0, -4) else -4
     
     # stepType 1 is for stepping between second and first semester
-    elif stepType == 1: return -5 if offset == 0 or offset == 6 else 6
+    elif stepType == 1: return -5 if offset in (0, 6) else 6
 
     # Return Error if code is altered to cause error
     else: raise SystemExit(f"Invalid 'stepType' in func 'stepIndex' line {getLineNumber()}")
diff --git a/tinker.py b/tinker.py
index bede172..aecc413 100644
--- a/tinker.py
+++ b/tinker.py
@@ -1,4 +1,4 @@
-#! python
+#!/usr/bin/env python
 from os.path import exists as file_exists
 from prettytable import PrettyTable
 from typing import Tuple
diff --git a/util/estimateGrade.py b/util/estimateGrade.py
index cf1213f..1a3a436 100644
--- a/util/estimateGrade.py
+++ b/util/estimateGrade.py
@@ -1,4 +1,4 @@
-#! python
+#!/usr/bin/env python
 import json
 
 # Get students
diff --git a/util/generateCourses.py b/util/generateCourses.py
index 276bd8c..a67f8c3 100644
--- a/util/generateCourses.py
+++ b/util/generateCourses.py
@@ -1,4 +1,4 @@
-#! python
+#!/usr/bin/env python
 import json
 import csv
 
diff --git a/util/mockStudents.py b/util/mockStudents.py
index 034c9cf..7286cbe 100644
--- a/util/mockStudents.py
+++ b/util/mockStudents.py
@@ -1,4 +1,4 @@
-#! python
+#!/usr/bin/env python
 import json
 import csv