code: def find_multiplicity(knot, knot_vector, **kwargs):
      
      # Get tolerance value
      tol = kwargs.get('tol', 10e-8)
  
      mult = 0  # initial multiplicity
  
      for kv in knot_vector:
          if abs(knot - kv) <= tol:
              mult += 1
  
      return mult
docs: Finds knot multiplicity over the knot vector.
  
      Keyword Arguments:
          * ``tol``: tolerance (delta) value for equality checking
  
      :param knot: knot or parameter, :math:`u`
      :type knot: float
      :param knot_vector: knot vector, :math:`U`
      :type knot_vector: list, tuple
      :return: knot multiplicity, :math:`s`
      :rtype: int