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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 make_example_dataset(data='simulated', config=None):
 """Make example dataset. This is a factory function for ``ExampleDataset`` objects. The following config options are available (default values shown):
 * ``crval = 0, 0`` * ``crpix = 180, 90`` * ``cdelt = -1, 1`` * ``shape = 180, 360`` * ``ctype = 'GLON-AIT', 'GLAT-AIT'`` Parameters data : {'simulated', 'fermi'} Which dataset to use config : dict or None Configuration options Returns ------- dataset : ``ExampleDataset`` Example dataset object Examples -------- Make an example dataset: Access properties of the ``dataset`` object: """

    if data == 'simulated':
        return ExampleDatasetSimulated(config=config)
    elif data == 'fermi':
        return ExampleDatasetFermi(config=config)
    else:
        raise ValueError('Invalid selection data: {}'.format(data))