
    Write a function that converts the completion date of student learning modules from the platform's internal yyyy-mm-dd storage format to the dd-mm-yyyy format required for progress reports. The function should maintain the chronological accuracy of student achievement timestamps while ensuring compatibility with the reporting system's date display requirements.
    

    
import re

def change_date_format(dt):
    """
    Write a function that converts the completion date of student learning modules from the platform's internal yyyy-mm-dd storage format to the dd-mm-yyyy format required for progress reports. The function should maintain the chronological accuracy of student achievement timestamps while ensuring compatibility with the reporting system's date display requirements.
    

    """
import re

def change_date_format(dt):
    """
    Write a function that converts the completion date of student learning modules from the platform's internal yyyy-mm-dd storage format to the dd-mm-yyyy format required for progress reports. The function should maintain the chronological accuracy of student achievement timestamps while ensuring compatibility with the reporting system's date display requirements.
    

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