'aggs': {
    'total': {
        'sum': {
            'field': 'amount'
         }
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}

'amount': {
    'type': 'double',
    'index': 'not_analyzed',
    'store': False
},

{
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    'aggregations': {'total': {'value': 21.0}},
    'hits': {'total': 1, 'max_score': 0.51623213,
    'hits': [
        {
            '_score': 0.51623213,
            '_index': 'crowdspire',
            '_type': 'donation',
            '_source': {
                'amount': 21.28,
                'created_on': '2019-06-15T01:37:42.451249+00:00'
            }
        }
    ]},
    'timed_out': False,
    '_shards': {'total': 5, 'successful': 5, 'skipped': 0, 'failed': 0}
}