**Use case**
I'm using `ip_trie` on maxmind geoip databases. Given an IP address I want to find out what key was used (ie what network the IP comes under). But it seems it is not possible to look up the key field when using `dictGet`?

```
        <layout>
            <ip_trie/>
        </layout>
        <structure>
            <key>
                <attribute>
                    <name>network</name>
                    <type>String</type>
                </attribute>
            </key>
            <attribute>
                <name>geoname_id</name>
                <type>UInt32</type>
                <null_value>0</null_value>
            </attribute>
...
```

```
clickhouse :) select dictGet('geoip_city_blocks_ipv4', 'geoname_id', tuple(toUInt32(toIPv4('1.1.1.1')))) ;

┌─dictGet('geoip_city_blocks_ipv4', 'geoname_id', tuple(toUInt32(toIPv4('1.1.1.1'))))─┐
│                                                                             2077456 │
└─────────────────────────────────────────────────────────────────────────────────────┘

clickhouse :) select dictGet('geoip_city_blocks_ipv4', 'network', tuple(toUInt32(toIPv4('1.1.1.1')))) ;

Received exception from server (version 20.11.3):
Code: 36. DB::Exception: Received from localhost:9000. DB::Exception: No such attribute 'network': While processing dictGet('geoip_city_blocks_ipv4', 'network', tuple(toUInt32(toIPv4('1.1.1.1')))). 
```

const StorageID & dict_id_,
    const DictionaryStructure & dict_struct_,
    DictionarySourcePtr source_ptr_,
    const DictionaryLifetime dict_lifetime_,
    bool require_nonempty_)
    : IDictionaryBase(dict_id_)
    , dict_struct(dict_struct_)
    , source_ptr{std::move(source_ptr_)}
    , dict_lifetime(dict_lifetime_)
    , require_nonempty(require_nonempty_)
    , logger(&Poco::Logger::get("IPAddressDictionary"))
{
    createAttributes();
    loadData();
    calculateBytesAllocated();
}
#define DECLARE(TYPE) \
    void IPAddressDictionary::get##TYPE( \
        const std::string & attribute_name, const Columns & key_columns, const DataTypes & key_types, ResultArrayType<TYPE> & out) const \