code: def _get_input_name(schema, input_idx):
      """Return the string representing the name of positional-only input to the operator.
      This function appends the double underscore `__`, that indicates via the mypy convention,
      that all inputs are positional-only. This happens also for the names introduced via schema.
  
      Parameters
      ----------
      schema : OpSchema
          schema to query
      input_idx : int
          Index of the input
      """
      if schema.HasInputDox():
          return f"__{schema.GetInputName(input_idx)}"
      if schema.MaxNumInput() == 1:
          return "__input"
      return f"__input_{input_idx}"
  
imports: from nvidia.dali import fn
label_desc: Use image node_id 4 for calling a global function with example usage: _get_input_name(schema, input_idx) and returns: str, input_idx, str, schema, str