code: def test_check_positive_check_scitype(scitype, mtype, fixture_index):
      """Tests that check_is_scitype correctly confirms the scitype of examples.
  
      Parameters
      ----------
      scitype : str - scitype of fixture
      mtype : str - mtype of fixture
      fixture_index : int - index of fixture tuple with that scitype and mtype
  
      Raises
      ------
      RuntimeError if scitype is not defined or has no mtypes or examples
      AssertionError if examples are not correctly identified
      error if check itself raises an error
      """
      if mtype in AMBIGUOUS_MTYPES:
          return None
  
      # retrieve fixture for checking
      fixture = get_examples(mtype=mtype, as_scitype=scitype).get(
          fixture_index
      )
  
      # todo: possibly remove this once all checks are defined
      check_is_defined = (mtype, scitype) in check_dict.keys()
  
      # check fixtures that exist against checks that exist, when full metadata is queried
      if fixture is not None and check_is_defined:
          check_result = check_is_scitype(
              fixture, scitype, return_metadata=True
          )
          if not check_result[0]:
              msg = (
                  f"check_is_scitype returns False on scitype {scitype}, mtype {mtype} "
                  f"fixture {fixture_index}, message: "
              )
              msg = msg + str(check_result[1])
          assert check_result[0], msg
          assert check_result[2]["mtype"] == mtype
  
      # check fixtures that exist against checks that exist, when no metadata is queried
      if fixture is not None and check_is_defined:
          check_result = check_is_scitype(
              fixture, scitype, return_metadata=[]
          )
          if not check_result[0]:
              msg = (
                  f"check_is_scitype returns False on scitype {scitype}, mtype {mtype} "
                  f"fixture {fixture_index}, message: "
              )
              msg = msg + str(check_result[1])
          assert check_result[0], msg
          assert check_result[2]["mtype"] == mtype
  
file_path: sktime/sktime/datatypes/tests/test_check.py
imports: import numpy
  from sktime.datatypes._check import AMBIGUOUS_MTYPES, check_dict, check_is_mtype, check_is_scitype
  from sktime.datatypes._check import mtype
  from sktime.datatypes._check import scitype
  from sktime.datatypes._examples import get_examples
  from sktime.datatypes._registry import SCITYPE_LIST, scitype_to_mtype
label_desc: Use image node_id 5 for calling a global function with example usage: test_check_positive_check_scitype(scitype, mtype, fixture_index) and returns: None