class_docstr: Class for Cifti2 header extension
class_docstr_tok: ["Class","for","Cifti2","header","extension"]
code: def may_contain_header(klass, binaryblock):
      if not super().may_contain_header(binaryblock):
          return False
      hdr = klass(binaryblock=binaryblock[: klass.sizeof_hdr])
      return klass._valid_intent_code(hdr.get_intent("code")[0])
  
imports: from io import BytesIO
  import numpy
  from packaging.version import Version, parse
  from ..None import xmlutils
  from ..batteryrunners import Report
  from ..nifti1 import Nifti1Extension, extension_codes, intent_codes
  from ..nifti2 import Nifti2Header, Nifti2Image
  from ..spatialimages import HeaderDataError
  from .cifti2 import CIFTI_BRAIN_STRUCTURES, CIFTI_MODEL_TYPES, Cifti2BrainModel, Cifti2Header, Cifti2HeaderError, Cifti2Label, Cifti2LabelTable, Cifti2Matrix, Cifti2MatrixIndicesMap, Cifti2MetaData, Cifti2NamedMap, Cifti2Parcel, Cifti2Surface, Cifti2TransformationMatrixVoxelIndicesIJKtoXYZ, Cifti2VertexIndices, Cifti2Vertices, Cifti2Volume, Cifti2VoxelIndicesIJK, _underscore
label_desc: Use image node_id 2 for calling the _Cifti2AsNiftiHeader obj's underlying member method code with example usage: obj.may_contain_header(klass, binaryblock) and returns: klass, False