code: def _verify_minute(
      self,
      calendar,
      minute,
      next_open_answer,
      prev_open_answer,
      next_close_answer,
      prev_close_answer,
  ):
      self.assertEqual(calendar.next_open(minute), next_open_answer)
  
      self.assertEqual(
          self.calendar.previous_open(minute), prev_open_answer
      )
  
      self.assertEqual(
          self.calendar.next_close(minute), next_close_answer
      )
  
      self.assertEqual(
          self.calendar.previous_close(minute), prev_close_answer
      )
  
imports: from datetime import time
  from os.path import abspath, dirname, join
  from unittest import TestCase
  import numpy
  import pandas
  from nose_parameterized import parameterized
  from pandas import read_csv
  from pandas.tslib import Timedelta
  from pandas.util.testing import assert_index_equal
  from pytz import timezone
  from toolz import concat
  from catalyst.errors import CalendarNameCollision, InvalidCalendarName
  from catalyst.testing.predicates import assert_equal
  from catalyst.utils.calendars import deregister_calendar, get_calendar, register_calendar
  from catalyst.utils.calendars.calendar_utils import _default_calendar_aliases, _default_calendar_factories, register_calendar_type
  from catalyst.utils.calendars.trading_calendar import days_at_time, TradingCalendar
label_desc: Use image node_id 6 for calling the ExchangeCalendarTestBase obj's underlying member method code with example usage: obj._verify_minute(calendar, minute, next_open_answer, prev_open_answer, next_close_answer, prev_close_answer) without return types