code: def testF90RealSingle(self):
      (p, r) = (6, 30)
      factory = MPI.Datatype.Create_f90_real
      args = (p, r)
      self.check(None, factory, *args)
  
imports: from mpi4py import MPI
  import mpiunittest
  import struct
label_desc: Use image node_id 16 for calling the BaseTestDatatypeCreateMixin obj's underlying member method code with example usage: obj.testF90RealSingle() without return types