code: def _get_derivative(coordinates):
      """Get derivative of the line from (0,0) to given coordinates.
  
      :param coordinates: A coordinate pair
      :type coordinates: tuple(float, float)
      :return: Derivative; inf if x is zero
      :rtype: float
      """
      try:
          return coordinates[1] / coordinates[0]
      except ZeroDivisionError:
          return float("inf")
  
file_path: nltk/nltk/metrics/paice.py
imports: from math import sqrt
label_desc: Use image node_id 4 for calling a global function with example usage: _get_derivative(coordinates) and returns: unknown, float