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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_volume(self,colorchange=True,column=None,name='',str='{name}',**kwargs):
 		""" 		Add 'volume' study to QuantFigure.studies 		Parameters: 			colorchange : bool 				If True then each volume bar will have a fill color 				depending on if 'base' had a positive or negative 				change compared to the previous value 				If False then each volume bar will have a fill color 				depending on if the volume data itself had a positive or negative 				change compared to the previous value 			column :string 				Defines the data column name that contains the volume data. 				Default: 'volume' 			name : string 				Name given to the study 			str : string 				Label factory for studies 				The following wildcards can be used: 					{name} : Name of the column 					{study} : Name of the study 					{period} : Period used 				Examples: 					'study: {study} - period: {period}' 			 		kwargs : 			base : string 				Defines the column which will define the 				positive/negative changes (if colorchange=True). 				Default = 'close' 			up_color : string 				Color for positive bars 			down_color : string 				Color for negative bars 		"""

		if not column:
			column=self._d['volume']
		up_color=kwargs.pop('up_color',self.theme['up_color'])
		down_color=kwargs.pop('down_color',self.theme['down_color'])
		study={'kind':'volume',
			   'name':name,
			   'params':{'colorchange':colorchange,'base':'close','column':column,
						 'str':None},
			  'display':utils.merge_dict({'up_color':up_color,'down_color':down_color},kwargs)}
		self._add_study(study)