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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 _load_or_get_from_model(self, var, start_date=None, end_date=None, time_offset=None, model=None, **DataAttrs):
 """Load a DataArray for the requested variable and time range Supports both access of grid attributes either through the DataLoader or through an optionally-provided Model object. Defaults to using the version found in the DataLoader first. """

        grid_attrs = None if model is None else model.grid_attrs

        try:
            return self.load_variable(
                var, start_date=start_date, end_date=end_date,
                time_offset=time_offset, grid_attrs=grid_attrs, **DataAttrs)
        except (KeyError, IOError) as e:
            if var.name not in GRID_ATTRS or model is None:
                raise e
            else:
                try:
                    return getattr(model, var.name)
                except AttributeError:
                    raise AttributeError(
                        'Grid attribute {} could not be located either '
                        'through this DataLoader or in the provided Model '
                        'object: {}.'.format(var, model))