from enum import Enum


def change_type_as_string(modification_type_enum_value: Enum) -> str:
    """
    Returns a string representing the value of PyDriller's ModificationType enum. 
    PyDriller does not make this enum publicly available to the outside world.
    """
    
    change_type = ""
    
    if (str(modification_type_enum_value) == "ModificationType.ADD"):
        change_type = "ADD"
    elif (str(modification_type_enum_value) == "ModificationType.COPY"):
        change_type = "COPY"
    elif (str(modification_type_enum_value) == "ModificationType.RENAME"):
        change_type = "RENAME"
    elif (str(modification_type_enum_value) == "ModificationType.DELETE"):
        change_type = "DELETE"
    elif (str(modification_type_enum_value) == "ModificationType.MODIFY"):
        change_type = "MODIFY"
    elif (str(modification_type_enum_value) == "ModificationType.UNKNOWN"):
        change_type = "UNKNOWN"
    
    return change_type