📇 Contact Manager – A Python CLI App

👨‍⚕️ About the Author

“Medical student who codes. Building health tech, one line at a time.”

I’m NaijaCodeClinician – a Nigerian, a future physician, and a self‑taught Python programmer.
I’m currently working through OpenStax Introduction to Python Programming. This is one of my first complete projects.
I believe the best doctors will also understand technology. Every line of code brings me closer to building tools that improve healthcare in Nigeria.

🧩 Project Description

Contact Manager is a command‑line application that lets you store, search, update, and delete contacts with phone and email validation.
It uses parallel lists (no dictionaries yet – I haven’t reached that chapter) and my own validation.py module for phone and email checks.

✨ Features

• ✅ Add a contact (name, phone number, optional email)
• ✅ View all contacts in a clean list
• ✅ Search contacts by partial name match
• ✅ Update phone number or email address
• ✅ Delete a contact with confirmation
• ✅ Phone validation – supports spaces, hyphens, leading +, length 5‑15
• ✅ Email validation – checks @, dot after @, and TLD letters
• ✅ Duplicate prevention (no duplicate names, phone numbers, or emails)
• ✅ Graceful exit with countdown

🚀 How to Run

1. Install Python 3 (I use Termux on Android, but it works on any system).
2. Clone this repository or download the two files:
   • contact_manager.py
   • validation.py
3. Open a terminal in the project folder and run:

   python contact_manager.py
   
   

🛠️ Dependencies

· Python 3 (standard library only – no external packages)

📁 Files

· contact_manager.py – main program · validation.py – phone and email validation logic (no regex, just loops and conditionals)

🔮 What I’ve Learned & Next Steps

This project taught me:

· How to structure a multi‑function program · Input validation without external libraries · The importance of flags (is_found, has_lower, etc.) · How to keep parallel lists in sync

Next improvements (when I learn more):

· Save contacts to a CSV file (Chapter 14 – Files) · Add a graphical interface with Flask (Chapter 15) · Replace parallel lists with dictionaries (Chapter 10)

💬 Feedback Welcome

I’m still learning, so any suggestions, code reviews, or ideas are highly appreciated. Feel free to open an issue or contact me via GitHub.

Author: NaijaCodeClinician

License: MIT