code: def is_integer(v):
      # type: (...) -> bool
      
      try:
          from builtins import int
          return isinstance(v, int)  # Match both int and long on Py2
      except ImportError:
          from past.builtins import long
          return isinstance(v, (int, long))
docs: Test whether a value is an integer (of any kind).
  
      Examples:
          >>> is_integer(1)
          True
          >>> is_integer(-0.123)
          False
          >>> is_integer(3.)
          False
          >>> is_integer(9223372036854775808)
          True
          >>> is_integer('1')
          False
          >>> is_integer(None)
          False
          >>> is_integer(numpy.int(3))
          True