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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 cast(cls, c):
 """Convert the first argument into a Complete object"""

        if isinstance(c, Complete):
            return c
        elif isinstance(c, Translation):
            return Complete(np.identity(3, float), c.t)
        elif isinstance(c, Rotation):
            return Complete(c.r, np.zeros(3, float))