text: import unittest
  import os
  import datetime
  import tempfile
  import shutil
  
  import numpy as np
  
  import desisurvey.ephem
  from desisurvey.test.base import Tester
  from desisurvey.forecast import Forecast
  
  
  class TestForecast(Tester):
  
      def test_forecast(self):
          gen = np.random.RandomState(123)
          ephem = desisurvey.ephem.get_ephem()
          W = gen.uniform(size=ephem.num_nights)
          tiles = desisurvey.tiles.get_tiles()
          HA = gen.normal(scale=15, size=tiles.ntiles)
          for twilight in True, False:
              forecast = Forecast(use_twilight=twilight, design_hourangle=HA, weather=W)
              forecast.summary()
  
  
  def test_suite():
      """Allows testing of only this module with the command::
  
          python setup.py test -m <modulename>
      """
      return unittest.defaultTestLoader.loadTestsFromName(__name__)
  