code: def _is_a(f, v):
      try:
          f(v)
      except ValueError:
          return False
      else:
          return True
  
imports: from __future__ import print_function
  import tokenize
  import six
  from six.moves import cStringIO
  from patsy import PatsyError
  from patsy.origin import Origin
  from patsy.infix_parser import Token, Operator, infix_parse, ParseNode
  from patsy.tokens import python_tokenize, pretty_untokenize
  from patsy.util import PushbackAdapter
label_desc: Use image node_id 1 for calling a global function with example usage: _is_a(f, v) and returns: True, False