nl: mapping is an dictionary with 8 initial entries: BLOCK_TAG_START for 'openblock', BLOCK_TAG_END for 'closeblock',
code: mapping = { 'openblock' : BLOCK_TAG_START , 'closeblock' : BLOCK_TAG_END , 'openvariable' : VARIABLE_TAG_START , 'closevariable' : VARIABLE_TAG_END , 'openbrace' : SINGLE_BRACE_START , 'closebrace' : SINGLE_BRACE_END , 'opencomment' : COMMENT_TAG_START , 'closecomment' : COMMENT_TAG_END , }