def insert_symbol(self, sname, skind, stype):
self.table.append(SymbolTableEntry(sname, skind, stype))<EOL>self.table_len = len(self.table)<EOL>return self.table_len-<NUM_LIT:1><EOL>
Inserts new symbol at the end of the symbol table.
           Returns symbol index
           sname - symbol name
           skind - symbol kind
           stype - symbol type