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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 get_original_order_unique_ids(id_array):
 """ Get the unique id's of id_array, in their original order of appearance. Parameters id_array : 1D ndarray. Should contain the ids that we want to extract the unique values from. Returns ------- original_order_unique_ids : 1D ndarray. Contains the unique ids from `id_array`, in their original order of appearance. """

    assert isinstance(id_array, np.ndarray)
    assert len(id_array.shape) == 1

    # Get the indices of the unique IDs in their order of appearance
    # Note the [1] is because the np.unique() call will return both the sorted
    # unique IDs and the indices
    original_unique_id_indices =\
        np.sort(np.unique(id_array, return_index=True)[1])

    # Get the unique ids, in their original order of appearance
    original_order_unique_ids = id_array[original_unique_id_indices]

    return original_order_unique_ids