def file_to_ints(input_file):
    """
    Input: A file containing one number per line
    Output: An int iterable
    Blank lines and lines starting with '#' are ignored
    """
    ints = []
    with open(input_file) as f:
        for line in f.readlines():
            line = line.strip()
            if line and not line.startswith('#'):
                ints.append(int(line))
    return ints