code: def joins_smoothly_with(self, previous, wrt_parameterization=False):
          
          if wrt_parameterization:
              return self.start == previous.end and np.isclose(
                  self.derivative(0), previous.derivative(1))
          else:
              return self.start == previous.end and np.isclose(
                  self.unit_tangent(0), previous.unit_tangent(1))
docs: Checks if this segment joins smoothly with previous segment.  By
          default, this only checks that this segment starts moving (at t=0) in
          the same direction (and from the same positive) as previous stopped
          moving (at t=1).  To check if the tangent magnitudes also match, set
          wrt_parameterization=True.