def find_indent(filename):
    """ Find the indent type of this file.

    This function assumes consistant indentation.

    Args:
        filename: The filename to look in.
    Returns:
        N spaces if indented with 2 or 4 spaces, or a tab char if indented
        with tabs.

    """
    with open(filename) as f:
        for l in f:
            if "\t" in l:
                return "\t"
            if "    " in l:
                return "    "
            if "  " in l:
                return "  "