code: def test_sources_merge_custom_ticker(self):
      requests_kwargs = {}
  
      def capture_kwargs(zelf, url, **kwargs):
          requests_kwargs.update(
              mask_requests_args(url, kwargs).requests_kwargs
          )
          return PALLADIUM_DATA
  
      # Patching fetch_url instead of using responses in this test so that we
      # can intercept the requests keyword arguments and confirm that they're
      # correct.
      with patch(
          "zipline.sources.requests_csv.PandasRequestsCSV.fetch_url",
          new=capture_kwargs,
      ):
          results = self.run_algo(
              """
  from zipline.api import fetch_csv, record, sid
  
  def rename_col(df):
      df = df.rename(columns={'New York 15:00': 'price'})
      df = df.fillna(method='ffill')
      return df[['price', 'sid']]
  
  def initialize(context):
      fetch_csv('https://dl.dropbox.com/u/16705795/PALL.csv',
          date_column='Date',
          symbol='palladium',
          post_func=rename_col,
          date_format='%Y-%m-%d'
          )
      context.stock = sid(24)
  
  def handle_data(context, data):
      record(palladium=data.current("palladium", "price"))
      record(aapl=data.current(context.stock, "price"))
          """
          )
  
          np.testing.assert_array_equal([24] * 251, results["aapl"])
          self.assertEqual(337, results["palladium"].iloc[-1])
  
          expected = {
              "allow_redirects": False,
              "stream": True,
              "timeout": 30.0,
          }
  
          self.assertEqual(expected, requests_kwargs)
  
imports: from nose_parameterized import parameterized
  import pandas
  import numpy
  from mock import patch
  from zipline.errors import UnsupportedOrderParameters
  from zipline.sources.requests_csv import mask_requests_args
  from zipline.utils import factory
  from zipline.testing import FetcherDataPortal
  from zipline.testing.fixtures import WithResponses, WithMakeAlgo, ZiplineTestCase
  from .resources.fetcher_inputs.fetcher_test_data import AAPL_CSV_DATA, AAPL_IBM_CSV_DATA, AAPL_MINUTE_CSV_DATA, CPIAUCSL_DATA, FETCHER_ALTERNATE_COLUMN_HEADER, FETCHER_UNIVERSE_DATA, FETCHER_UNIVERSE_DATA_TICKER_COLUMN, MULTI_SIGNAL_CSV_DATA, NON_ASSET_FETCHER_UNIVERSE_DATA, PALLADIUM_DATA, NFLX_DATA
label_desc: Use image node_id 10 for calling the FetcherTestCase obj's underlying member method code with example usage: obj.test_sources_merge_custom_ticker() and returns: PALLADIUM_DATA