README.md in woothee-1.7.0 vs README.md in woothee-1.8.0

@@ -54,10 +54,10 @@
 require 'woothee'
 Woothee.is_crawler("Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 6.1; Trident/4.0)")
  # => false
 ```
 
-Try to see useragent's category is 'crawler' or not, by casual(fast) method. Minor case of crawlers is not tested in this method. To check crawler strictly, use `Woothee.parse(str)[:category] == 'crawler'`.
+Try to see useragent's category is 'crawler' or not, by casual(fast) method. Minor case of crawlers is not tested in this method. To check crawler strictly, use `Woothee.parse(str)[:category] == :crawler`.
 
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 ## Authors