docstr: Returns unique element for each list in the column, order for each
  unique element is not guaranteed.
  
  Returns
  -------
  ListColumn
  
  Examples
  --------
  >>> s = cudf.Series([[1, 1, 2, None, None], None, [4, 4], []])
  >>> ds = dask_cudf.from_cudf(s, 2)
  >>> ds
  0    [1.0, 1.0, 2.0, nan, nan]
  1                         None
  2                   [4.0, 4.0]
  3                           []
  dtype: list
  >>> ds.list.unique().compute() # Order of elements not guaranteed
  0              [1.0, 2.0, nan]
  1                         None
  2                        [4.0]
  3                           []
  dtype: list
docstr_tok: ["Returns","unique","element","for","each","list","in","the","column",",","order","for","each","unique","element","is","not","guaranteed",".","Returns","--","--","--","-","ListColumn","Examples","--","--","--","--",">",">",">","s","=","cudf.Series","(","[","[","1",",","1",",","2",",","None",",","None","]",",","None",",","[","4",",","4","]",",","[","]","]",")",">",">",">","ds","=","dask_cudf.from_cudf","(","s",",","2",")",">",">",">","ds","0","[","1.0",",","1.0",",","2.0",",","nan",",","nan","]","1","None","2","[","4.0",",","4.0","]","3","[","]","dtype",":","list",">",">",">","ds.list.unique","(",")",".compute","(",")","#","Order","of","elements","not","guaranteed","0","[","1.0",",","2.0",",","nan","]","1","None","2","[","4.0","]","3","[","]","dtype",":","list"]
code: def unique(self):
      """
      Returns unique element for each list in the column, order for each
      unique element is not guaranteed.
  
      Returns
      -------
      ListColumn
  
      Examples
      --------
      >>> s = cudf.Series([[1, 1, 2, None, None], None, [4, 4], []])
      >>> ds = dask_cudf.from_cudf(s, 2)
      >>> ds
      0    [1.0, 1.0, 2.0, nan, nan]
      1                         None
      2                   [4.0, 4.0]
      3                           []
      dtype: list
      >>> ds.list.unique().compute() # Order of elements not guaranteed
      0              [1.0, 2.0, nan]
      1                         None
      2                        [4.0]
      3                           []
      dtype: list
      """
      return self.d_series.map_partitions(
          lambda s: s.list.unique(), meta=self.d_series._meta
      )
  
file_path: cudf/python/dask_cudf/dask_cudf/accessors.py
label_desc: Use image node_id 7 for calling the ListMethods obj's underlying member method code with example usage: obj.unique() and returns: self