text: from fast_arrow.resources.option_chain import OptionChain
  from tests.test_util import gen_vcr, gen_client
  
  
  class TestPosition(object):
  
      def test_fetch_fields(self):
          client = gen_client()
  
          oc_id = "644f21f0-a166-4c94-bd67-02568d3a5940"
          oc_symbol = "TLT"
  
          with gen_vcr().use_cassette('option_chain_fetch.yaml'):
              chain = OptionChain.fetch(client, oc_id, oc_symbol)
  
              expected_fields = [
                  'can_open_position', 'symbol', 'trade_value_multiplier',
                  'underlying_instruments', 'expiration_dates', 'cash_component',
                  'min_ticks', 'id']
  
              actual_fields = list(chain.keys())
  
              assert(set(expected_fields) == set(actual_fields))
  