code: def testInvalidInstrument(self):
      instrument = "inexistent"
  
      # Don't skip errors.
      with self.assertRaisesRegexp(
          Exception, "404 Client Error: Not Found"
      ):
          with common.TmpDir() as tmpPath:
              quandl.build_feed(
                  instrument,
                  [instrument],
                  2010,
                  2010,
                  tmpPath,
                  bar.Frequency.WEEK,
                  authToken=QUANDL_API_KEY,
              )
  
      # Skip errors.
      with common.TmpDir() as tmpPath:
          bf = quandl.build_feed(
              instrument,
              [instrument],
              2010,
              2010,
              tmpPath,
              bar.Frequency.WEEK,
              skipErrors=True,
              authToken=QUANDL_API_KEY,
          )
          bf.loadAll()
          self.assertNotIn(instrument, bf)
  
imports: import os
  import datetime
  import tempfile
  import shutil
  import subprocess
  import six
  from .None import common
  from pyalgotrade.tools import quandl
  from pyalgotrade import bar
  from pyalgotrade.barfeed import quandlfeed
label_desc: Use image node_id 8 for calling the ToolsTestCase obj's underlying member method code with example usage: obj.testInvalidInstrument() without return types