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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 _all_feature_values( self, column, feature, distinct=True, contig=None, strand=None):
 """ Cached lookup of all values for a particular feature property from the database, caches repeated queries in memory and stores them as a CSV. Parameters column : str Name of property (e.g. exon_id) feature : str Type of entry (e.g. exon) distinct : bool, optional Keep only unique values contig : str, optional Restrict query to particular contig strand : str, optional Restrict results to "+" or "-" strands Returns a list constructed from query results. """

        return self.db.query_feature_values(
            column=column,
            feature=feature,
            distinct=distinct,
            contig=contig,
            strand=strand)