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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 rotation_from_axes(x_axis, y_axis, z_axis):
 """Convert specification of axis in target frame to a rotation matrix from source to target frame. Parameters x_axis : :obj:`numpy.ndarray` of float A normalized 3-vector for the target frame's x-axis. y_axis : :obj:`numpy.ndarray` of float A normalized 3-vector for the target frame's y-axis. z_axis : :obj:`numpy.ndarray` of float A normalized 3-vector for the target frame's z-axis. Returns ------- :obj:`numpy.ndarray` of float A 3x3 rotation matrix that transforms from a source frame to the given target frame. """

        return np.hstack((x_axis[:,np.newaxis], y_axis[:,np.newaxis], z_axis[:,np.newaxis]))