Mexico, Italy duplicate data issue

[ionecum]

Some Italian "states" are, in reality, "boroughs". This makes that some cities are duplicated.

For example this
{
"id": 137775,
"name": "Città metropolitana di Milano",
"latitude": "45.45186000",
"longitude": "9.14586000"
},

which is also duplicated in English
{
"id": 1698,
"name": "Metropolitan City of Milan",
"state_code": "MI",
"cities": []
},

and this, which is not mentioned as a state, but as a city of Lombardy
{
"id": 140142,
"name": "Milan",
"latitude": "45.46427000",
"longitude": "9.18951000"
},

3 entries of the same city. This is awful.

ANY CITY MUST BE UNIQUELY IDENTIFIED AND MENTIONED IN THE DATA BASE.

Also some boroughs in Mexico City are duplicated. For example
{
"id": 68588,
"name": "Benito Juarez",
"latitude": "19.39840000",
"longitude": "-99.15766000"
},
{
"id": 68597,
"name": "Benito Juárez",
"latitude": "19.37270000",
"longitude": "-99.15640000"
},

Duplicate data is perhaps the most serious issue in any database.