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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 ytickangle(self, angle, index=1):
 """Set the angle of the y-axis tick labels. Parameters value : int Angle in degrees index : int, optional Y-axis index Returns ------- Chart """

        self.layout['yaxis' + str(index)]['tickangle'] = angle
        return self