class_docstr: Represents an input source for a `DAGPipeline`.
  
  Give an `DagInput` instance to `DAGPipeline` by connecting `Pipeline` objects
  to it in the DAG.
  
  When `DAGPipeline.transform` is called, the input object
  will be fed to any Pipeline instances connected to an
  `DagInput` given in the DAG.
  
  The type given to `DagInput` will be the `DAGPipeline`'s `input_type`.
class_docstr_tok: ["Represents","an","input","source","for","a","`","DAGPipeline","`",".","Give","an","`","DagInput","`","instance","to","`","DAGPipeline","`","by","connecting","`","Pipeline","`","objects","to","it","in","the","DAG",".","When","`","DAGPipeline.transform","`","is","called",",","the","input","object","will","be","fed","to","any","Pipeline","instances","connected","to","an","`","DagInput","`","given","in","the","DAG",".","The","type","given","to","`","DagInput","`","will","be","the","`","DAGPipeline","`","'s","`","input_type","`","."]
code: def __repr__(self):
      return "DagInput(%s)" % self.output_type
  
imports: from __future__ import absolute_import
  from __future__ import division
  from __future__ import print_function
  import itertools
  from magenta.pipelines import pipeline
  import six
label_desc: Use image node_id 4 for calling the DagInput obj's underlying member method code with example usage: obj.__repr__() and returns: unknown