code: def testHT_DCPERIOD(self):
      ds = self.__loadMedPriceDS()
      self.assertAmountsAreEqual(
          indicator.HT_DCPERIOD(ds, 252)[32], 15.5527, 4
      )
      self.assertAmountsAreEqual(
          indicator.HT_DCPERIOD(ds, 252)[-1], 18.6140, 4
      )
  
imports: import datetime
  import talib
  from six.moves import xrange
  from .None import common
  from pyalgotrade.talibext import indicator
  from pyalgotrade import bar
  from pyalgotrade import dataseries
  from pyalgotrade.dataseries import bards
label_desc: Use image node_id 22 for calling the TestCase obj's underlying member method code with example usage: obj.testHT_DCPERIOD() without return types