def _check_symbols(self, symbols):
if len(symbols) != self.size:<EOL><INDENT>raise TypeError("<STR_LIT>"<EOL>"<STR_LIT>")<EOL><DEDENT>for symbol in symbols:<EOL><INDENT>if not isinstance(symbol, str):<EOL><INDENT>raise TypeError("<STR_LIT>")<EOL><DEDENT><DEDENT>
the size must be the same as the length of the array numbers and all elements must be strings