def parse_so_terms(so_file):
    """Retrieve all available Sequence Ontology terms from the file.
    """
    so_terms = []
    with open(so_file) as in_handle:
        for line in in_handle:
            if line.find('name:') == 0:
                name = line[5:].strip()
                so_terms.append(name)
    return so_terms