def normalize(text, replacement_tuples=[]):
    """Normalize Arabic text by replacing complex characters by simple ones.

    Args:
        text (str): the string that needs to be normalized
        replacement_tuples (list of tuple pairs): (character, replacement)

    Examples:
        >>> normalize('AlphaBet', [("A", "a"), ("B", "b")])
        'alphabet'
    """
    for char, repl in replacement_tuples:
        text = text.replace(char, repl)
    return text
