class_docstr: `CallSignature` objects is the return value of `Script.function_definition`.
  It knows what functions you are currently in. e.g. `isinstance(` would
  return the `isinstance` function. without `(` it would return nothing.
class_docstr_tok: ["`","CallSignature","`","objects","is","the","return","value","of","`","Script.function_definition","`",".","It","knows","what","functions","you","are","currently","in",".","e.g",".","`","isinstance","(","`","would","return","the","`","isinstance","`","function",".","without","`","(","`","it","would","return","nothing","."]
docstr: The Param index of the current call.
  Returns None if the index cannot be found in the curent call.
docstr_tok: ["The","Param","index","of","the","current","call",".","Returns","None","if","the","index","can","not","be","found","in","the","curent","call","."]
code: def index(self):
      """
      The Param index of the current call.
      Returns None if the index cannot be found in the curent call.
      """
      if self._key_name_str is not None:
          for i, param in enumerate(self.params):
              if self._key_name_str == param.name:
                  return i
          if self.params:
              param_name = self.params[-1]._name
              if param_name.tree_name is not None:
                  if (
                      param_name.tree_name.get_definition().star_count
                      == 2
                  ):
                      return i
          return None
  
      if self._index >= len(self.params):
          for i, param in enumerate(self.params):
              tree_name = param._name.tree_name
              if tree_name is not None:
                  # *args case
                  if tree_name.get_definition().star_count == 1:
                      return i
          return None
      return self._index
  
imports: import re
  from parso.python.tree import search_ancestor
  from jedi import settings
  from jedi.evaluate.utils import ignored, unite
  from jedi.cache import memoize_method
  from jedi.evaluate import imports
  from jedi.evaluate import compiled
  from jedi.evaluate.imports import ImportName
  from jedi.evaluate.context import instance
  from jedi.evaluate.context import ClassContext, FunctionExecutionContext
  from jedi.api.keywords import KeywordName
label_desc: Use image node_id 2 for calling the CallSignature obj's underlying member method code with example usage: obj.index() and returns: self, None, None, i, i, i