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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 axisar(axis, angle):
 """ Construct a rotation matrix that rotates vectors by a specified angle about a specified axis. http://naif.jpl.nasa.gov/pub/naif/toolkit_docs/C/cspice/axisar_c.html :param axis: Rotation axis. :type axis: 3 Element vector (list, tuple, numpy array) :param angle: Rotation angle, in radians. :type angle: float :return: Rotation matrix corresponding to axis and angle. :rtype: numpy array ((3, 3)) """

    axis = stypes.toDoubleVector(axis)
    angle = ctypes.c_double(angle)
    r = stypes.emptyDoubleMatrix()
    libspice.axisar_c(axis, angle, r)
    return stypes.cMatrixToNumpy(r)