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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 _apply_rotation(self,dx,dy):
 """ private method to rotate points according to Vario2d.bearing and Vario2d.anisotropy Parameters dx : (float or numpy.ndarray) x-coordinates to rotate dy : (float or numpy.ndarray) y-coordinates to rotate Returns ------- dxx : (float or numpy.ndarray) rotated x-coordinates dyy : (float or numpy.ndarray) rotated y-coordinates """

        if self.anisotropy == 1.0:
            return dx,dy
        rcoefs = self.rotation_coefs
        dxx = (dx * rcoefs[0]) +\
             (dy * rcoefs[1])
        dyy = ((dx * rcoefs[2]) +\
             (dy * rcoefs[3])) *\
             self.anisotropy
        return dxx,dyy