class_docstr: A protocol for representing nested sequences.
  
  Warning
  -------
  `_NestedSequence` currently does not work in combination with typevars,
  *e.g.* ``def func(a: _NestedSequnce[T]) -> T: ...``.
  
  See Also
  --------
  collections.abc.Sequence
      ABCs for read-only and mutable :term:`sequences`.
  
  Examples
  --------
  .. code-block:: python
  
      >>> from __future__ import annotations
  
      >>> from typing import TYPE_CHECKING
      >>> import numpy as np
      >>> from numpy._typing import _NestedSequence
  
      >>> def get_dtype(seq: _NestedSequence[float]) -> np.dtype[np.float64]:
      ...     return np.asarray(seq).dtype
  
      >>> a = get_dtype([1.0])
      >>> b = get_dtype([[1.0]])
      >>> c = get_dtype([[[1.0]]])
      >>> d = get_dtype([[[[1.0]]]])
  
      >>> if TYPE_CHECKING:
      ...     reveal_locals()
      ...     # note: Revealed local types are:
      ...     # note:     a: numpy.dtype[numpy.floating[numpy._typing._64Bit]]
      ...     # note:     b: numpy.dtype[numpy.floating[numpy._typing._64Bit]]
      ...     # note:     c: numpy.dtype[numpy.floating[numpy._typing._64Bit]]
      ...     # note:     d: numpy.dtype[numpy.floating[numpy._typing._64Bit]]
docstr: Implement ``x in self``.
code: def __contains__(self, x: object, /) -> bool:
      """Implement ``x in self``."""
      raise NotImplementedError
  
file_path: numpy/numpy/_typing/_nested_sequence.py
imports: from __future__ import annotations
  from collections.abc import Iterator
  from typing import Any, TypeVar, Protocol, runtime_checkable
label_desc: Use image node_id 3 for calling the _NestedSequence obj's underlying member method code with example usage: obj.__contains__() without return types