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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 point(self, pos):
 """Calculate the x,y position at a certain position of the path"""

        return ((1 - pos) ** 3 * self.start) + \
               (3 * (1 - pos) ** 2 * pos * self.control1) + \
               (3 * (1 - pos) * pos ** 2 * self.control2) + \
               (pos ** 3 * self.end)