
    Write a function to convert a user's profile creation date from the database format (yyyy-mm-dd) to the user-friendly display format (dd-mm-yyyy) for showing when potential friend connections joined the social network. The converted date format will be used across user profiles, friend suggestions, and activity timelines to maintain consistent date presentation throughout the platform.
    

    
import re

def change_date_format(dt):
    """
    Write a function to convert a user's profile creation date from the database format (yyyy-mm-dd) to the user-friendly display format (dd-mm-yyyy) for showing when potential friend connections joined the social network. The converted date format will be used across user profiles, friend suggestions, and activity timelines to maintain consistent date presentation throughout the platform.
    

    """
import re

def change_date_format(dt):
    """
    Write a function to convert a user's profile creation date from the database format (yyyy-mm-dd) to the user-friendly display format (dd-mm-yyyy) for showing when potential friend connections joined the social network. The converted date format will be used across user profiles, friend suggestions, and activity timelines to maintain consistent date presentation throughout the platform.
    

    """
    return re.sub('(\\d{4})-(\\d{1,2})-(\\d{1,2})', '\\3-\\2-\\1', dt)