def remove_blank_lines(self):
to_remove = []<EOL>for i, line in enumerate(self):<EOL><INDENT>ln = line.strip()<EOL>if ln == '<STR_LIT>':<EOL><INDENT>to_remove.append(i)<EOL><DEDENT><DEDENT>self.delete_lines(to_remove)<EOL>
Remove all blank lines (blank lines are those with zero characters).