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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 dot(self, b, out=None):
 """dot product of two arrays. Refer to `numpy.dot` for full documentation. See Also -------- numpy.dot : equivalent function Examples -------- [[2. 2.] [2. 2.]] km*s This array method can be conveniently chained: [[8. 8.] [8. 8.]] km*s**2 """

        res_units = self.units * getattr(b, "units", NULL_UNIT)
        ret = self.view(np.ndarray).dot(np.asarray(b), out=out) * res_units
        if out is not None:
            out.units = res_units
        return ret