def replace_chars(target_str, char_list, replacement_str):
    """
    Replaces characters in a given string with a given string
    :param target_str: string - String needing character replacement
    :param char_list: list - List of characters to be replaced
    :param replacement_str: string - String to replace given characters
    """
    for char in char_list:
        target_str = target_str.replace(char, replacement_str)
    return target_str