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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def connect():
 	""" 	establish connection to frontend notebook 	"""

	if not is_notebook():
		print('Python session is not running in a Notebook Kernel')
		return
	
	global _comm

	kernel=get_ipython().kernel
	kernel.comm_manager.register_target('tdb',handle_comm_opened)
	# initiate connection to frontend.
	_comm=Comm(target_name='tdb',data={})
	# bind recv handler
	_comm.on_msg(None)