def get_sep(file_path: str) -> str:
    """Figure out the sep based on file name. Only helps with tsv and csv.

    Args:
        file_path: Path of file.

    Returns: sep

    """
    if file_path[-4:] == '.tsv':
        return '\t'
    elif file_path[-4:] == '.csv':
        return ','
    raise ValueError('Input file is not a .csv or .tsv')