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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 get_truncation_language() -> ParserElement: """Build a parser for protein truncations."""

    l1 = truncation_tag + nest(amino_acid(AMINO_ACID) + ppc.integer(TRUNCATION_POSITION))
    l1.setParseAction(_handle_trunc)
    l2 = truncation_tag + nest(ppc.integer(TRUNCATION_POSITION))
    l2.setParseAction(_handle_trunc_legacy)
    return l1 | l2