message: Fix array casting
diff: @@ -110,7 +110,7 @@ class SupersetDataFrame(object):
  # need to do this because we can not specify a mixed dtype when
  # instantiating the DataFrame, and this allows us to have different
  # dtypes for each column.
  - array = np.array(data)
  + array = np.array(data, dtype="object")
  data = {
  column: pd.Series(array[:, i], dtype=dtype[column])
  for i, column in enumerate(column_names)
  