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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 filter_by_gene_expression( self, gene_expression_dict, min_expression_value=0.0):
 """ Filters effects to those which have an associated gene whose expression value in the gene_expression_dict argument is greater than min_expression_value. Parameters gene_expression_dict : dict Dictionary mapping Ensembl gene IDs to expression estimates (either FPKM or TPM) min_expression_value : float Threshold above which we'll keep an effect in the result collection """

        return self.filter_above_threshold(
            key_fn=lambda effect: effect.gene_id,
            value_dict=gene_expression_dict,
            threshold=min_expression_value)