docs: def tree(self):
          """Like tree view mode
          """
          self.msg.template(78)
          print("| Dependencies\n"
                "| -- Packages")
          self.msg.template(78)
          self.data()
          for pkg, dep in self.dmap.iteritems():
              print("+ {0}{1}{2}".format(self.green, pkg, self.endc))
              print("|")
              for d in dep:
                  print("+-- {0}".format(d))
                  print("|")
              sys.stdout.write("\x1b[1A{0}\n".format(" "))
              sys.stdout.flush()
          self.summary()
          if self.image:
              Graph(self.image).dependencies(self.dmap)