def sum_to_num(max_number):
    """
    Returns the sum from 0 to max_number inclusive.

    >>> from gender_novels.testing import tests
    >>> x = tests.sum_to_num(3)
    >>> x
    6

    >>> x = tests.sum_to_num(100)
    >>> x
    5050
    """
    sum_result = 0
    for n in range(max_number + 1):
        sum_result += n
    return sum_result