Returns data (value) associated with a given key of a given key-value store. Check detailed documentation for explanation
{"key_value_store_address":"<key-value-store-address>","keys":[{"key_hex":"5C21010901000000"},{"key_json":{"kind":"Tuple","fields":[{"kind":"U32","value":"1"}]}}]}
defines upper boundary (inclusive) for queried data. i.e { "at_state_version" = {"epoch" = 10} }
, will return data till 10 epoch.