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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 add_trendline(self,date0,date1,on='close',text=None,**kwargs):
 		""" 		Adds a trendline to the QuantFigure. 		Given 2 dates, the trendline is connected on the data points 		that correspond to those dates. 		Parameters: 			date0 : string 				Trendline starting date 			date1 : string 				Trendline end date 			on : string 				Indicate the data series in which the 				trendline should be based. 					'close' 					'high' 					'low' 					'open' 			text : string 				If passed, then an annotation will be added 				to the trendline (at mid point) 		kwargs: 			from_strfmt : string 				Defines the date formating in which 				date0 and date1 are stated. 				default: '%d%b%y'					 			to_strfmt : string 				Defines the date formatting 				to which it should be converted. 				This should match the same format as the timeseries index. 				default : '%Y-%m-%d'		 		"""

		d={'kind':'trend','date0':date0,'date1':date1,'on':on,'text':text}
		d.update(**kwargs)
		self.trendlines.append(d)