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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 _indexes(arr):
 """ Returns the list of all indexes of the given array. Currently works for one and two-dimensional arrays """

    myarr = np.array(arr)
    if myarr.ndim == 1:
        return list(range(len(myarr)))
    elif myarr.ndim == 2:
        return tuple(itertools.product(list(range(arr.shape[0])),
                                       list(range(arr.shape[1]))))
    else:
        raise NotImplementedError('Only supporting arrays of dimension 1 and 2 as yet.')