code: def _W4(N: int, k: Array) -> Array:
      N_arr, k = promote_dtypes_complex(N, k)
      return jnp.exp(-0.5j * jnp.pi * k / N_arr)
  
file_path: jax/jax/_src/scipy/fft.py
imports: from __future__ import annotations
  from collections.abc import Sequence
  from functools import partial
  import math
  import scipy.fft
  from jax import lax
  import jax.numpy
  from jax._src.util import canonicalize_axis
  from jax._src.numpy.util import _wraps, promote_dtypes_complex
  from jax._src.typing import Array
label_desc: Use image node_id 1 for calling a global function with example usage: _W4(N, k) and returns: jnp