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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 dataset_exists(dataset, data_home=None):
 """ Checks to see if a directory with the name of the specified dataset exists in the data home directory, found with ``get_data_home``. Parameters dataset : str The name of the dataset; should either be a folder in data home or specified in the yellowbrick.datasets.DATASETS variable. data_home : str, optional The path on disk where data is stored. If not passed in, it is looked up from YELLOWBRICK_DATA or the default returned by ``get_data_home``. Returns ------- exists : bool If a folder with the dataset name is in the data home directory. """

    data_home = get_data_home(data_home)
    path = os.path.join(data_home, dataset)

    return os.path.exists(path) and os.path.isdir(path)