Modified logic to start up the web server if no arguments are given.

SQLAlchemy.py

@@ -6,7 +6,7 @@
 
 from sqlalchemy import create_engine, Column, Integer, String, Float, DateTime, ForeignKey
 from sqlalchemy.orm import sessionmaker, relationship, declarative_base
-
+from flask import Flask, render_template
 
 # In[ ]:
 
@@ -92,8 +92,22 @@ import sys
 # Create a command-line tool that parses sys.argv to allow a user to create/edit/delete user objects.
 
 if len(sys.argv) < 2:
-    print("Usage: python script.py [create|edit|delete] [username] [credentials]")
-    sys.exit(1)
+    app = Flask(__name__)
+
+    # Create a database connection
+    engine = create_engine('sqlite:///user_database.db')
+    Session = sessionmaker(bind=engine)
+    session = Session()
+
+    @app.route('/')
+    def home():
+        # Get all user objects
+        users = session.query(User).all()
+        return render_template('index.html', users=users)
+
+    app.run()
+
+
 
 command = sys.argv[1]
 
@@ -149,33 +163,4 @@ elif command == "delete":
         print("User not found!")
 
 else:
-    print("Invalid command!")
-
-
-# In[ ]:
-
-
-from flask import Flask, render_template
-from sqlalchemy import create_engine
-from sqlalchemy.orm import sessionmaker
-
-
-# In[ ]:
-
-
-app = Flask(__name__)
-
-# Create a database connection
-engine = create_engine('sqlite:///user_database.db')
-Session = sessionmaker(bind=engine)
-session = Session()
-
-@app.route('/')
-def home():
-    # Get all user objects
-    users = session.query(User).all()
-    return render_template('index.html', users=users)
-
-if __name__ == '__main__':
-    app.run()
-
+    print("Usage: python script.py [create|edit|delete] [username] [credentials]")