A vector of variable Id's.Use search_variables or
get_variables to find variable id code.
lang
A language of returned data, "pl" (default), "en"
...
Other arguments passed on to GET. For example
a proxy parameters, see details.
Details
To use a proxy to connect, a use_proxy can be
passed to GET. For example
get_request(id, filters,
config = httr::use_proxy(url, port, username, password)).