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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 contains(self, seqid, start, end, overlap=True):
 """This returns a list of GFF objects which cover a specified location. :param seqid: The landmark identifier (usually a chromosome) :param start: The 1-based position of the start of the range we are querying :param end: The 1-based position of the end of the range we are querying :param overlap: A boolean value, if true we allow features to overlap the query range. For instance, overlap=True with the range (5,10), will return a GFF object spanning from (8,15). overlap=False will only return objects fully containing the range. :return: A list of GFF objects """

        d = self.positions.get(seqid,[])
        if overlap:
            return [gff_object for gff_start, gff_end in d
                    for gff_object in d[(gff_start, gff_end)]
                    if not (end <= gff_start or start >= gff_end)]
        else:
            return [gff_object for gff_start, gff_end in d
                    for gff_object in d[(gff_start, gff_end)]
                    if (gff_start <= start and gff_end >= end)]