class_docstr: Poly-encoder Agent.
  
  Equivalent of bert_ranker/polyencoder and biencoder_multiple_output but does not
  rely on an external library (hugging face).
class_docstr_tok: ["Poly-encoder","Agent",".","Equivalent","of","bert_ranker\/polyencoder","and","biencoder_multiple_output","but","does","not","rely","on","an","external","library","(","hugging","face",")","."]
docstr: Create the input context value for the model.
  
  Must return a dictionary.  This will be passed directly into the model via
  `**kwargs`, i.e.,
  
  >>> model(**_model_context_input(batch))
  
  This is intentionally overridable so that richer models can pass additional
  inputs.
docstr_tok: ["Create","the","input","context","value","for","the","model",".","Must","return","a","dictionary",".","This","will","be","passed","directly","into","the","model","via","`","*","*","kwargs","`",",","i.e.",",",">",">",">","model","(","*","*","_model_context_input","(","batch",")",")","This","is","intentionally","overridable","so","that","richer","models","can","pass","additional","inputs","."]
code: def _model_context_input(self, batch) -> Dict[str, Any]:
      """
      Create the input context value for the model.
  
      Must return a dictionary.  This will be passed directly into the model via
      `**kwargs`, i.e.,
  
      >>> model(**_model_context_input(batch))
  
      This is intentionally overridable so that richer models can pass additional
      inputs.
      """
      return {"ctxt_tokens": batch.text_vec}
  
imports: from parlai.core.params import ParlaiParser
  from typing import Any, Dict, Optional, Tuple
  import torch
  from parlai.core.opt import Opt
  from parlai.core.torch_ranker_agent import TorchRankerAgent
  from parlai.core.torch_agent import Batch
  from parlai.utils.misc import recursive_getattr
  from parlai.utils.logging import logging
  from .biencoder import AddLabelFixedCandsTRA
  from .modules import BasicAttention, MultiHeadAttention, TransformerEncoder
  from .transformer import TransformerRankerAgent
label_desc: Use image node_id 15 for calling the PolyencoderAgent obj's underlying member method code with example usage: obj._model_context_input(batch) and returns: dict