code: def test_boolean_dtype(all_parsers):
      parser = all_parsers
      data = "\n".join(
          [
              "a",
              "True",
              "TRUE",
              "true",
              "1",
              "1.0",
              "False",
              "FALSE",
              "false",
              "0",
              "0.0",
              "NaN",
              "nan",
              "NA",
              "null",
              "NULL",
          ]
      )
  
      result = parser.read_csv(StringIO(data), dtype="boolean")
      expected = DataFrame(
          {
              "a": pd.array(
                  [
                      True,
                      True,
                      True,
                      True,
                      True,
                      False,
                      False,
                      False,
                      False,
                      False,
                      None,
                      None,
                      None,
                      None,
                      None,
                  ],
                  dtype="boolean",
              )
          }
      )
  
      tm.assert_frame_equal(result, expected)
  
imports: from collections import defaultdict
  from io import StringIO
  import numpy
  import pytest
  from pandas.errors import ParserWarning
  import pandas
  from pandas import DataFrame, Timestamp
  import pandas._testing
  from pandas.core.arrays import ArrowStringArray, IntegerArray, StringArray
label_desc: Use image node_id 7 for calling a global function with example usage: test_boolean_dtype(all_parsers) without return types