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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 _axis_in_detector(geometry):
 """A vector in the detector plane that points along the rotation axis."""

    du, dv = geometry.det_axes_init
    axis = geometry.axis
    c = np.array([np.vdot(axis, du), np.vdot(axis, dv)])
    cnorm = np.linalg.norm(c)

    # Check for numerical errors
    assert cnorm != 0

    return c / cnorm