<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def variant_matches_reference_sequence(variant, ref_seq_on_transcript, strand):
 """ Make sure that reference nucleotides we expect to see on the reference transcript from a variant are the same ones we encounter. """

    if strand == "-":
        ref_seq_on_transcript = reverse_complement_dna(ref_seq_on_transcript)
    return ref_seq_on_transcript == variant.ref