foo 1, b:2
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Groovy script
  Call expression
    Reference expression
      PsiElement(identifier)('foo')
    PsiWhiteSpace(' ')
    Command arguments
      Literal
        PsiElement(Integer)('1')
      PsiElement(,)(',')
      PsiWhiteSpace(' ')
      Named argument
        Argument label
          PsiElement(identifier)('b')
        PsiElement(:)(':')
        Literal
          PsiElement(Integer)('2')