def insert_separator(string):
    """
    Inserts the apropriate separator before the first encontered non-digit non-space caracter (letter)
    """
    insert_at = 0
    for i in range(0, len(string)):
        c = string[i]
        if not (c.isdigit() or c == " ") and insert_at == 0:
            insert_at = i
    return string[:insert_at] + "\t" + string[insert_at:]