code: def postgresql_uuid_ossp(self):
      def check_uuid_ossp(config):
          if not exclusions.against(config, "postgresql"):
              return False
          try:
              config.db.execute("SELECT uuid_generate_v4()")
              return True
          except:
              return False
  
      return exclusions.only_if(check_uuid_ossp)
  
imports: from sqlalchemy import exc
  from sqlalchemy import Index
  from sqlalchemy import text
  from alembic.testing import exclusions
  from alembic.testing.requirements import SuiteRequirements
  from alembic.util import compat
  from alembic.util import sqla_compat
label_desc: Use image node_id 33 for calling the DefaultRequirements obj's underlying member method code with example usage: obj.postgresql_uuid_ossp() and returns: exclusions, False, True, False