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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 trim_variant_fields(location, ref, alt):
 """ Trims common prefixes from the ref and alt sequences Parameters location : int Position (starting from 1) on some chromosome ref : str Reference nucleotides alt : str Alternate (mutant) nucleotide Returns adjusted triplet (location, ref, alt) """

    if len(alt) > 0 and ref.startswith(alt):
        # if alt is a prefix of the ref sequence then we actually have a
        # deletion like:
        #   g.10 GTT > GT
        # which can be trimmed to
        #   g.12 'T'>''
        ref = ref[len(alt):]
        location += len(alt)
        alt = ""
    if len(ref) > 0 and alt.startswith(ref):
        # if ref sequence is a prefix of the alt sequence then we actually have
        # an insertion like:
        #   g.10 GT>GTT
        # which can be trimmed to
        #   g.11 ''>'T'
        # Note that we are selecting the position *before* the insertion
        # (as an arbitrary convention)
        alt = alt[len(ref):]
        location += len(ref) - 1
        ref = ""
    return location, ref, alt