0_sourece_name_country_city_quantity.json

[
    {"name": "Amina Frost", "country": "US", "city": "Hammond", "amount": 30},
    {"name": "Mehak Flowers", "country": "US", "city": "Kansas City", "amount": 41},
    {"name": "Angharad Davie", "country": "AU", "city": "Queenstown", "amount": 31},
    {"name": "Hannah Robins", "country": "UK", "city": "Langport", "amount": 1},
    {"name": "Romilly Lowe", "country": "US", "city": "Kansas City", "amount": 10},
    {"name": "Komal Donaldson", "country": "UK", "city": "Langport", "amount": 19},
    {"name": "Florence Andrew", "country": "US", "city": "Kansas City", "amount": 7}
]

1_expected_result_entries_group_by_country.json

{
  "US": [
    {"name": "Amina Frost", "country": "US", "city": "Hammond", "amount": 30},
    {"name": "Mehak Flowers", "country": "US", "city": "Kansas City", "amount": 41},
    {"name": "Romilly Lowe", "country": "US", "city": "Kansas City", "amount": 10},
    {"name": "Florence Andrew", "country": "US", "city": "Kansas City", "amount": 7}
  ],
  "UK": [
    {"name": "Hannah Robins", "country": "UK", "city": "Langport", "amount": 1},
    {"name": "Komal Donaldson", "country": "UK", "city": "Langport", "amount": 19}
  ],
  "AU": [
    {"name": "Angharad Davie", "country": "AU", "city": "Queenstown", "amount": 31}
  ]
}

2_expected_result_sum_group_by_country_and_city_rollup_for_city.json

{
  "US": {
    "Hammond": 30,
    "Kansas City": 58,
    "all": 88
  },
  "UK": {
    "Langport": 20,
    "all": 20
  },
  "AU": {
    "Queenstown": 31,
    "all": 31
  }
}