code: def generate(env):
      
      global PDFAction
      if PDFAction is None:
          PDFAction = SCons.Action.Action('$DVIPDFCOM', '$DVIPDFCOMSTR')
  
      global DVIPDFAction
      if DVIPDFAction is None:
          DVIPDFAction = SCons.Action.Action(DviPdfFunction, strfunction = DviPdfStrFunction)
  
      from . import pdf
      pdf.generate(env)
  
      bld = env['BUILDERS']['PDF']
      bld.add_action('.dvi', DVIPDFAction)
      bld.add_emitter('.dvi', PDFEmitter)
  
      env['DVIPDF']      = 'dvipdf'
      env['DVIPDFFLAGS'] = SCons.Util.CLVar('')
      env['DVIPDFCOM']   = 'cd ${TARGET.dir} && $DVIPDF $DVIPDFFLAGS ${SOURCE.file} ${TARGET.file}'
  
      # Deprecated synonym.
      env['PDFCOM']      = ['$DVIPDFCOM']
docs: Add Builders and construction variables for dvipdf to an Environment.