### Question:
Symbol extends ERE { @Override public ERE copy() { return this; } private  Symbol(); static Symbol get(String name); @Override EREType getEREType(); @Override boolean equals(Object o); @Override int compareTo(Object o); @Override ERE copy(); @Override String toString(); @Override boolean containsEpsilon(); @Override ERE derive(Symbol s);  }### Answer:
@Test public void testCopy() { ERE copy = one.copy(); assertEquals(one, copy); }