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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 from_start_and_end(cls, start, end, sequence, helix_type='b_dna', phos_3_prime=False):
 """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. """

        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