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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 Open(pathfileext=None, shot=None, t=None, Dt=None, Mesh=None, Deg=None, Deriv=None, Sep=True, Pos=True, OutPath=None, ReplacePath=None, Ves=None, out='full', Verb=False, Print=True):
 """ Open a ToFu object saved file This generic open function identifies the required loading routine by detecting how the object was saved from the file name extension. If pathfileext is not provided (None), then the following keyword arguments are fed to :meth:`~tofu.pathfile.FindSolFile()`: shot, t, Dt, Mesh, Deg, Deriv, Sep, Pos Parameters pathfileext : None / str If provided, the name of the file to load OutPath : None / str If provided, the absolute path where the file is to be found ReplacePath : str If provided, ? (to finish) Ves : None / If provided, the :class:`tofu.geom.Ves` object that shall be used to reconstruct the object (if not provided, the appropriate vessel will be loaded). out : str Flag indicating whether the object should be loaded completely ('full'), in a light dismissing the heaviest attributes ('light') or whether only the Id or a list of Id should be returned ('Id'), valid only for '.npz' Verb : bool Flag indicating whether to pring intermediate comments on the loading procedure Returns ------- obj ToFu object The loaded and re-created ToFu object """

    assert None in [pathfileext,shot] and not (pathfileext is None and shot is None), "Arg pathfileext or shot must be None, but not both !"
    if pathfileext is None:
        File = FindSolFile(shot=shot, t=t, Dt=Dt, Mesh=Mesh, Deg=Deg,
                           Deriv=Deriv, Sep=Sep, Pos=Pos, OutPath=OutPath)
        if File is None:
            return File
        pathfileext = os.path.join(OutPath,File)
    C = any([ss in pathfileext for ss in ['.npz']])
    assert C, "Arg pathfileext must contain '.npz' !"

    if '.npz' in pathfileext:
        obj = _open_np(pathfileext, Ves=Ves, ReplacePath=ReplacePath,
                       out=out, Verb=Verb, Print=Print)
    if Print:
        print("Loaded :  "+pathfileext)
    return obj