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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 get_frames(self, frames='all', override=False, **kwargs):
 """ Extract frames from the trajectory file. Depending on the passed parameters a frame, a list of particular frames, a range of frames (from, to), or all frames can be extracted with this function. Parameters frames : :class:`int` or :class:`list` or :class:`touple` or :class:`str` Specified frame (:class:`int`), or frames (:class:`list`), or range (:class:`touple`), or `all`/`everything` (:class:`str`). (default=`all`) override : :class:`bool` If True, a frame already storred in :attr:`frames` can be override. (default=False) extract_data : :class:`bool`, optional If False, a frame is returned as a :class:`str` block as in the trajectory file. Ohterwise, it is extracted and returned as :class:`pywindow.molecular.MolecularSystem`. (default=True) swap_atoms : :class:`dict`, optional If this kwarg is passed with an appropriate dictionary a :func:`pywindow.molecular.MolecularSystem.swap_atom_keys()` will be applied to the extracted frame. forcefield : :class:`str`, optional If this kwarg is passed with appropriate forcefield keyword a :func:`pywindow.molecular.MolecularSystem.decipher_atom_keys()` will be applied to the extracted frame. Returns ------- :class:`pywindow.molecular.MolecularSystem` If a single frame is extracted. None : :class:`NoneType` If more than one frame is extracted, the frames are returned to :attr:`frames` """

        if override is True:
            self.frames = {}
        if isinstance(frames, int):
            frame = self._get_frame(
                self.trajectory_map[frames], frames, **kwargs)
            if frames not in self.frames.keys():
                self.frames[frames] = frame
            return frame
        if isinstance(frames, list):
            for frame in frames:
                if frame not in self.frames.keys():
                    self.frames[frame] = self._get_frame(
                        self.trajectory_map[frame], frame, **kwargs)
        if isinstance(frames, tuple):
            for frame in range(frames[0], frames[1]):
                if frame not in self.frames.keys():
                    self.frames[frame] = self._get_frame(
                        self.trajectory_map[frame], frame, **kwargs)
        if isinstance(frames, str):
            if frames in ['all', 'everything']:
                for frame in range(0, self.no_of_frames):
                    if frame not in self.frames.keys():
                        self.frames[frame] = self._get_frame(
                            self.trajectory_map[frame], frame, **kwargs)