class_docstr: Start node for a set of Streams
  
  Source nodes emit data into other nodes. They typically get this data
  by polling external sources, and are necessarily run by an event loop.
  
  Parameters
  ----------
  start: bool
      Whether to call the run method immediately. If False, nothing
      will happen until ``source.start()`` is called.
class_docstr_tok: ["Start","node","for","a","set","of","Streams","Source","nodes","emit","data","into","other","nodes",".","They","typically","get","this","data","by","polling","external","sources",",","and","are","necessarily","run","by","an","event","loop",".","Parameters","--","--","--","--","--","start",":","bool","Whether","to","call","the","run","method","immediately",".","If","False",",","nothing","will","happen","until","``","source.start","(",")","``","is","called","."]
code: def __init__(self, start=False, **kwargs):
      self.stopped = True
      super().__init__(ensure_io_loop=True, **kwargs)
      self.started = False
      if start:
          self.start()
  
imports: import asyncio
  from glob import glob
  import queue
  import os
  import time
  from tornado import gen
  import weakref
  from .core import Stream, convert_interval, RefCounter, sync
label_desc: Use image node_id 1 to create a new Source object from inherited base classes: Stream with example: obj = Source(start)