Part of the series

Several example codes

~2 min read · Updated Oct 1, 2025

Program Overview

This Python program receives a list of groups and displays:
- The total number of groups
- The names of groups that appear on the timeline (based on activity timestamps)
For simplicity, the data is structured as a list of dictionaries containing group names and timestamps.


Python Code:


# Sample list of groups with timestamps
groups = [
    {"name": "Math Group", "timestamp": "2025-09-30 10:00"},
    {"name": "Physics Group", "timestamp": "2025-09-30 11:30"},
    {"name": "Programming Group", "timestamp": "2025-10-01 09:15"},
]

# Count total groups
group_count = len(groups)

# Extract timeline group names
timeline_groups = [group["name"] for group in groups]

# Display results
print(f"Total number of groups: {group_count}")
print("--- Timeline Groups ---")
for name in timeline_groups:
    print(name)

Sample Output:


Total number of groups: 3  
--- Timeline Groups ---  
Math Group  
Physics Group  
Programming Group

Step-by-Step Explanation:

- The data is defined as a list of dictionaries with group names and timestamps
- len() is used to count the total number of groups
- A list comprehension extracts the names of all timeline groups
- The output is printed in a clean, readable format


Written & researched by Dr. Shahin Siami

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