code: def initialize_api(context):
      context.incr = 0
      context.sale_price = None
      set_slippage(FixedSlippage())
  
imports: import numpy
  from nose.tools import assert_raises
  from six import itervalues
  from zipline.algorithm import TradingAlgorithm
  from zipline.api import FixedSlippage, order, set_slippage, record, sid
  from zipline.errors import UnsupportedOrderParameters
  from zipline.finance.execution import LimitOrder, MarketOrder, StopLimitOrder, StopOrder
label_desc: Use image node_id 3 for calling a global function with example usage: initialize_api(context) without return types