code: def test_cutoff_to_index():
      dr = date_range("20000101", periods=3000, freq="W")
      y = Series(np.arange(3000.0), index=dr)
      date_index = y.index
      assert cutoff_to_index(1000, date_index, 0) == 1000
      assert cutoff_to_index(int(1000), date_index, 0) == 1000
      assert cutoff_to_index(np.int16(1000), date_index, 0) == 1000
      assert cutoff_to_index(np.int64(1000), date_index, 0) == 1000
      assert cutoff_to_index(date_index[1000], date_index, 0) == 1000
      assert cutoff_to_index(None, date_index, 1000) == 1000
  
imports: from abc import abstractmethod
  import datetime
  import numpy
  from numpy.random import RandomState
  from numpy.testing import assert_equal
  from pandas import DataFrame, Series, Timedelta, date_range
  import pytest
  from arch import doc
  from arch.univariate.base import implicit_constant
  from arch.utility.array import ConcreteClassMeta, DocStringInheritor, cutoff_to_index, date_to_index, ensure1d, ensure2d, find_index, parse_dataframe
label_desc: Use image node_id 10 for calling a global function with example usage: test_cutoff_to_index() without return types