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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 translate_variant_reads( variant, variant_reads, protein_sequence_length, transcript_id_whitelist=None, min_alt_rna_reads=MIN_ALT_RNA_READS, min_variant_sequence_coverage=MIN_VARIANT_SEQUENCE_COVERAGE, min_transcript_prefix_length=MIN_TRANSCRIPT_PREFIX_LENGTH, max_transcript_mismatches=MAX_REFERENCE_TRANSCRIPT_MISMATCHES, include_mismatches_after_variant=INCLUDE_MISMATCHES_AFTER_VARIANT, variant_sequence_assembly=VARIANT_SEQUENCE_ASSEMBLY):
 """ Given a variant and its associated alt reads, construct variant sequences and translate them into Translation objects. Returns 0 or more Translation objects. Parameters variant : varcode.Variant variant_reads : sequence or generator AlleleRead objects supporting the variant protein_sequence_length : int Try to translate protein sequences of this length, though sometimes we'll have to return something shorter (depending on the RNAseq data, and presence of stop codons). transcript_id_whitelist : set, optional If given, expected to be a set of transcript IDs which we should use for determining the reading frame around a variant. If omitted, then try to use all overlapping reference transcripts. min_alt_rna_reads : int Drop variant sequences from loci with fewer than this number of RNA reads supporting the alt allele. min_variant_sequence_coverage : int Trim variant sequences to nucleotides covered by at least this many reads. min_transcript_prefix_length : int Minimum number of bases we need to try matching between the reference context and variant sequence. max_transcript_mismatches : int Don't try to determine the reading frame for a transcript if more than this number of bases differ. include_mismatches_after_variant : bool Include mismatches after the variant locus in the count compared against max_transcript_mismatches. variant_sequence_assembly : bool Use overlap assembly to construct longer variant cDNA sequences. """

    if len(variant_reads) == 0:
        logger.info("No supporting reads for variant %s", variant)
        return []

    # Adding an extra codon to the desired RNA sequence length in case we
    # need to clip nucleotides at the start/end of the sequence
    cdna_sequence_length = (protein_sequence_length + 1) * 3

    variant_sequences = reads_to_variant_sequences(
        variant=variant,
        reads=variant_reads,
        preferred_sequence_length=cdna_sequence_length,
        min_alt_rna_reads=min_alt_rna_reads,
        min_variant_sequence_coverage=min_variant_sequence_coverage,
        variant_sequence_assembly=variant_sequence_assembly)

    if not variant_sequences:
        logger.info("No spanning cDNA sequences for variant %s", variant)
        return []

    # try translating the variant sequences from the same set of
    # ReferenceContext objects, which requires using the longest
    # context_size to be compatible with all of the sequences. Some
    # sequences maybe have fewer nucleotides than this before the variant
    # and will thus have to be trimmed.
    context_size = max(
        len(variant_sequence.prefix)
        for variant_sequence in variant_sequences)

    reference_contexts = reference_contexts_for_variant(
        variant,
        context_size=context_size,
        transcript_id_whitelist=transcript_id_whitelist)

    return list(translation_generator(
        variant_sequences=variant_sequences,
        reference_contexts=reference_contexts,
        min_transcript_prefix_length=min_transcript_prefix_length,
        max_transcript_mismatches=max_transcript_mismatches,
        include_mismatches_after_variant=include_mismatches_after_variant,
        protein_sequence_length=protein_sequence_length))