Remove copy method that was previously missed.

jplag.frontend.python-3/src/main/java/jplag/python3/Python3Token.java

@@ -1,7 +1,5 @@
 package jplag.python3;
 
-import jplag.Token;
-
 public class Python3Token extends jplag.Token implements Python3TokenConstants {
 
     private static final long serialVersionUID = 1485877548175917943L;
@@ -118,9 +116,4 @@ public class Python3Token extends jplag.Token implements Python3TokenConstants {
     public static int numberOfTokens() {
         return NUM_DIFF_TOKENS;
     }
-
-    @Override
-    public Token copy() {
-        return new Python3Token(type, file, line, column, length);
-    }
 }