     * isStrictSupersetOf
     * isDisjointWith
 */
+// Data
+var rows = [
+    ["column_1" : "Obi-Wan",   "column_2" : "Kenobi"],
+    ["column_1" : "Darth",     "column_2" : "Vader"],
+    ["column_1" : "Anakin",    "column_2" : "Skywalker"],
+    ["column_1" : "Darth",     "column_2" : "Sidious"],
+    ["column_1" : "Padme",     "column_2" : "Amidala"],
+    ["column_1" : "Mace",      "column_2" : "Windu"],
+    ["column_1" : "Count",     "column_2" : "Dooku"],
+    ["column_1" : "Luke",      "column_2" : "Skywalker"],
+    ["column_1" : "Han",       "column_2" : "Solo"],
+    ["column_1" : "Leia",      "column_2" : "Organa"],
+    ["column_1" : "Chew",      "column_2" : "Bacca"],
+    ["column_1" : "Boba",      "column_2" : "Fett"],
+    ["column_1" : "Lando",     "column_2" : "Calrissian"],
+    ["column_1" : "Kylo",      "column_2" : "Ren"],
+    ["column_1" : "Poe",       "column_2" : "Dameron"],
+    ["column_1" : "Finn",      "column_2" : "FN-2187"],
+    ["column_1" : "Rey",       "column_2" : "Rey"]
+]
+
+// Data Types
 typealias StudentKey    = String
 typealias StudentValue  = String
 typealias Student       = [StudentKey:StudentValue]

}

var mathBoys = Class()
mathBoys.insert(students[13]["name"]!)
mathBoys.insert(students[0]["name"]!)
mathBoys.insert(students[7]["name"]!)
mathBoys.insert(students[6]["name"]!)
mathBoys.insert(students[4]["name"]!)

var mathGirls = Class()
mathGirls.insert(students[11]["name"]!)
mathGirls.insert(students[8]["name"]!)

if mathGirls.isStrictSubsetOf(math) {
    print("Math girls is a strict subset of math")

classes["Engligh"] = english
classes["History"] = history

print("All \(rows.count) students")
for student in rows {
    print("\t\(student["name"]!)")
}

