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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_sparse(arr, kind='block', fill_value=None, dtype=None, copy=False):
 """ Convert ndarray to sparse format Parameters arr : ndarray kind : {'block', 'integer'} fill_value : NaN or another value dtype : np.dtype, optional copy : bool, default False Returns ------- (sparse_values, index, fill_value) : (ndarray, SparseIndex, Scalar) """


    arr = _sanitize_values(arr)

    if arr.ndim > 1:
        raise TypeError("expected dimension <= 1 data")

    if fill_value is None:
        fill_value = na_value_for_dtype(arr.dtype)

    if isna(fill_value):
        mask = notna(arr)
    else:
        # cast to object comparison to be safe
        if is_string_dtype(arr):
            arr = arr.astype(object)

        if is_object_dtype(arr.dtype):
            # element-wise equality check method in numpy doesn't treat
            # each element type, eg. 0, 0.0, and False are treated as
            # same. So we have to check the both of its type and value.
            mask = splib.make_mask_object_ndarray(arr, fill_value)
        else:
            mask = arr != fill_value

    length = len(arr)
    if length != len(mask):
        # the arr is a SparseArray
        indices = mask.sp_index.indices
    else:
        indices = mask.nonzero()[0].astype(np.int32)

    index = _make_index(length, indices, kind)
    sparsified_values = arr[mask]
    if dtype is not None:
        sparsified_values = astype_nansafe(sparsified_values, dtype=dtype)
    # TODO: copy
    return sparsified_values, index, fill_value