code: def sign(x: float):
      """Sign function.
  
      Parameters
      ----------
      x
  
      """
      return -1 if x < 0 else (1 if x > 0 else 0)
  
imports: from __future__ import annotations
  import functools
  import itertools
  import math
  import operator
  import numpy
  import scipy
label_desc: Use image node_id 12 for calling a global function with example usage: sign(x) and returns: unknown