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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 queryset(self, request, queryset):
 """Filter queryset using params from the form."""

        if self.form.is_valid():
            # get no null params
            filter_params = dict(
                filter(lambda x: bool(x[1]), self.form.cleaned_data.items())
            )
            return queryset.filter(**filter_params)
        return queryset