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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 optimize_filter_dict(filter_dict, trgm=True):
 """Improve query speed for a Django queryset `filter` or `exclude` kwargs dict WARNING: Wtthout `trgm`, this only improves the speed of exclude filters by 0.4% Arguments: filter_dict (dict):
 kwargs for Django ORM queryset `filter` and `exclude` queries trgm (bool):
 whether to assume the Django ORM trigram (djorm-trgm) extension is available Examples: True True True """

    optimized = {}
    for k, v in filter_dict.iteritems():
        if k.endswith('__in'):
            v = set(v)
            if len(v) == 1:
                optimized[k[:-4]] = tuple(v)[0]
            else:
                optimized[k] = v
        else:
            optimized[k] = v
    # This is the only optimization that actuall does some good
    if trgm:
        optimized_copy = dict(optimized)
        for k, v in optimized_copy.iteritems():
            if k.endswith('__contains'):
                optimized[k[:-10] + '__similar'] = v
            elif k.endswith('__icontains'):
                optimized[k[:-11] + '__similar'] = v
    return optimized