code: def preemphasis(
      y: np.ndarray,
      *,
      coef: float = ...,
      zi: Optional[ArrayLike] = ...,
      return_zf: Literal[True],
  ) -> Tuple[np.ndarray, np.ndarray]:
      ...
  
imports: import numpy
  import scipy.signal
  from .None import core
  from .None import decompose
  from .None import feature
  from .None import util
  from .util.exceptions import ParameterError
  from typing import Any, Callable, Iterable, Optional, Tuple, Union, overload
  from typing_extensions import Literal
  from numpy.typing import ArrayLike
label_desc: Use image node_id 11 for calling a global function with example usage: preemphasis(y) without return types