def _atom_to_filename(atom):
    """Translate an atom to a filename.

   :param atom: filename as atom
   :type atom: Term
   :return: filename as string
   :rtype: str
    """
    atomstr = str(atom)
    if atomstr[0] == atomstr[-1] == "'":
        atomstr = atomstr[1:-1]
    return atomstr
