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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 _find_only_image_column(sframe):
 """ Finds the only column in `sframe` with a type of turicreate.Image. If there are zero or more than one image columns, an exception will be raised. """

    from turicreate import Image
    return _find_only_column_of_type(sframe, target_type=Image,
                                     type_name='image', col_name='feature')