Extracting a usm names list from an usms.xml file
get_usms_list(file, usm = NULL)A vector of usm names
path <- get_examples_path(file_type = "xml")
usms_list <- get_usms_list(file = file.path(path, "usms.xml"))
usms_list <- get_usms_list(
file = file.path(path, "usms.xml"),
usm = c("usm1", "usm2")
)