
    Write a function to convert student essay submission dates from the academic management system's internal format (yyyy-mm-dd) to the institution's standard display format (dd-mm-yyyy) for academic reports. The function should handle all valid submission dates and maintain proper date formatting for consistent record-keeping across the institution's reporting system.
    

    
import re

def change_date_format(dt):
    """
    Write a function to convert student essay submission dates from the academic management system's internal format (yyyy-mm-dd) to the institution's standard display format (dd-mm-yyyy) for academic reports. The function should handle all valid submission dates and maintain proper date formatting for consistent record-keeping across the institution's reporting system.
    

    """
import re

def change_date_format(dt):
    """
    Write a function to convert student essay submission dates from the academic management system's internal format (yyyy-mm-dd) to the institution's standard display format (dd-mm-yyyy) for academic reports. The function should handle all valid submission dates and maintain proper date formatting for consistent record-keeping across the institution's reporting system.
    

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