code: def from_start_and_end(cls, start, end, sequence, helix_type='b_dna',
                             phos_3_prime=False):
          
          start = numpy.array(start)
          end = numpy.array(end)
          instance = cls(sequence, helix_type=helix_type,
                         phos_3_prime=phos_3_prime)
          instance.move_to(start=start, end=end)
          return instance
docs: Generates a helical `Polynucleotide` that is built along an axis.
  
          Parameters
          ----------
          start: [float, float, float]
              Start of the build axis.
          end: [float, float, float]
              End of build axis.
          sequence: str
              The nucleotide sequence of the nucleic acid.
          helix_type: str
              The type of nucleic acid helix to generate.
          phos_3_prime: bool
              If false the 5' and the 3' phosphor will be omitted.