code: def __contains__(self, other):
      if super(Float64Index, self).__contains__(other):
          return True
  
      try:
          # if other is a sequence this throws a ValueError
          return np.isnan(other) and self.hasnans
      except ValueError:
          try:
              return (
                  len(other) <= 1 and ibase._try_get_item(other) in self
              )
          except TypeError:
              pass
      except TypeError:
          pass
  
      return False
  
imports: import warnings
  import numpy
  from pandas._libs import index
  import pandas.compat
  from pandas.util._decorators import Appender, cache_readonly
  from pandas.core.dtypes.common import is_bool, is_bool_dtype, is_dtype_equal, is_extension_array_dtype, is_float, is_integer_dtype, is_scalar, needs_i8_conversion, pandas_dtype
  import pandas.core.dtypes.concat
  from pandas.core.dtypes.missing import isna
  from pandas.core import algorithms
  import pandas.core.common
  import pandas.core.indexes.base
  from pandas.core.indexes.base import Index, InvalidIndexError, _index_shared_docs
  from pandas.core.ops import get_op_result_name
label_desc: Use image node_id 8 for calling the Float64Index obj's underlying member method code with example usage: obj.__contains__(other) and returns: False, True, unknown, unknown