class_docstr: Test common dtype coercion rules between concat and append.
class_docstr_tok: ["Test","common","dtype","coercion","rules","between","concat","and","append","."]
code: def test_union_categorical_same_categories_different_order(self):
      # https://github.com/pandas-dev/pandas/issues/19096
      a = Series(
          Categorical(["a", "b", "c"], categories=["a", "b", "c"])
      )
      b = Series(
          Categorical(["a", "b", "c"], categories=["b", "a", "c"])
      )
      result = pd.concat([a, b], ignore_index=True)
      expected = Series(
          Categorical(
              ["a", "b", "c", "a", "b", "c"], categories=["a", "b", "c"]
          )
      )
      tm.assert_series_equal(result, expected)
  
imports: import numpy
  import pytest
  import pandas
  from pandas import Categorical, DataFrame, Index, Series
  import pandas._testing
label_desc: Use image node_id 12 for calling the TestConcatAppendCommon obj's underlying member method code with example usage: obj.test_union_categorical_same_categories_different_order() without return types