code: def dynkin_diagram(self):
      n = self.n
      diag = " " * 8 + str(2) + "\n"
      diag += " " * 8 + "0\n"
      diag += " " * 8 + "|\n"
      diag += " " * 8 + "|\n"
      diag += "---".join("0" for i in range(1, n)) + "\n"
      diag += "1   " + "   ".join(str(i) for i in range(3, n + 1))
      return diag
  
file_path: sympy/sympy/liealgebras/type_e.py
imports: from .cartan_type import Standard_Cartan
  from sympy.core.backend import eye, Rational
label_desc: Use image node_id 9 for calling the TypeE obj's underlying member method code with example usage: obj.dynkin_diagram() and returns: diag