def find_overlapping_location(feature, locations):
    """Finds the index of a gene location containing `feature`.

    Args:
        feature (SeqFeature): Feature being matched to a location
        locations (list): Start and end coordinates of gene features
    Returns:
        int: Index of matching start/end, if any
        None: No match found
    """
    for index, (start, end) in enumerate(locations):
        if feature.location.start >= start and feature.location.end <= end:
            return index