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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, phos_3_prime=False):
 """Creates a DNA duplex from a start and end point. Parameters start: [float, float, float] Start of the build axis. end: [float, float, float] End of build axis. sequence: str Nucleotide sequence. phos_3_prime: bool, optional If false the 5' and the 3' phosphor will be omitted."""

        strand1 = NucleicAcidStrand.from_start_and_end(
            start, end, sequence, phos_3_prime=phos_3_prime)
        duplex = cls(strand1)
        return duplex