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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 _check_dedup(data):
 """Check configuration for de-duplication. Defaults to no de-duplication for RNA-seq and small RNA, the back compatible default. Allow overwriting with explicit `mark_duplicates: true` setting. Also defaults to false for no alignment inputs. """

    if dd.get_analysis(data).lower() in ["rna-seq", "smallrna-seq"] or not dd.get_aligner(data):
        dup_param = utils.get_in(data, ("config", "algorithm", "mark_duplicates"), False)
    else:
        dup_param = utils.get_in(data, ("config", "algorithm", "mark_duplicates"), True)
    if dup_param and isinstance(dup_param, six.string_types):
        logger.info("Warning: bcbio no longer support explicit setting of mark_duplicate algorithm. "
                    "Using best-practice choice based on input data.")
        dup_param = True
    return dup_param