title: Eclipse & Groovy - unable to resolve class
body: <p>I am new to groovy and eclipse. I am going through a few tutorials and one of them calls for a groovy.xml.MarkupBuilder class to be imported but I get the following error message "Groovy:unable to resolve class groovy.xml.MarkupBuilder". What am I doing wrong?</p>
  
  <p>I have the following installed: 
  - Eclipse (2019-09)
  - Groovy Development Tools (3.6.0SNAPSHOT)
  - Groovy Version: 3.0.0-rc-1
  - JVM: 13.0.1</p>
  
  <p><a href="https://i.stack.imgur.com/TsYuT.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/TsYuT.jpg" alt="enter image description here"></a>
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