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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def view(molecule, viewer=settings['defaults']['viewer'], use_curr_dir=False):
 """View your molecule or list of molecules. .. note:: This function writes a temporary file and opens it with an external viewer. If you modify your molecule afterwards you have to recall view in order to see the changes. Args: molecule: Can be a cartesian, or a list of cartesians. viewer (str):
 The external viewer to use. The default is specified in settings.viewer use_curr_dir (bool):
 If True, the temporary file is written to the current diretory. Otherwise it gets written to the OS dependendent temporary directory. Returns: None: """

    try:
        molecule.view(viewer=viewer, use_curr_dir=use_curr_dir)
    except AttributeError:
        if pd.api.types.is_list_like(molecule):
            cartesian_list = molecule
        else:
            raise ValueError('Argument is neither list nor Cartesian.')
        if use_curr_dir:
            TEMP_DIR = os.path.curdir
        else:
            TEMP_DIR = tempfile.gettempdir()

        def give_filename(i):
            filename = 'ChemCoord_list_' + str(i) + '.molden'
            return os.path.join(TEMP_DIR, filename)

        i = 1
        while os.path.exists(give_filename(i)):
            i = i + 1

        to_molden(cartesian_list, buf=give_filename(i))

        def open_file(i):
            """Open file and close after being finished."""
            try:
                subprocess.check_call([viewer, give_filename(i)])
            except (subprocess.CalledProcessError, FileNotFoundError):
                raise
            finally:
                if use_curr_dir:
                    pass
                else:
                    os.remove(give_filename(i))
        Thread(target=open_file, args=(i,)).start()