
    Write a function that converts social event dates from the platform's internal database format (yyyy-mm-dd) to a user-friendly display format (dd-mm-yyyy) for the event calendar interface. The function should handle all valid event dates and maintain the proper ordering of day, month, and year components when displaying upcoming social gatherings to users.
    

    
import re

def change_date_format(dt):
    """
    Write a function that converts social event dates from the platform's internal database format (yyyy-mm-dd) to a user-friendly display format (dd-mm-yyyy) for the event calendar interface. The function should handle all valid event dates and maintain the proper ordering of day, month, and year components when displaying upcoming social gatherings to users.
    

    """
import re

def change_date_format(dt):
    """
    Write a function that converts social event dates from the platform's internal database format (yyyy-mm-dd) to a user-friendly display format (dd-mm-yyyy) for the event calendar interface. The function should handle all valid event dates and maintain the proper ordering of day, month, and year components when displaying upcoming social gatherings to users.
    

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