parameters: (environment, seq)
docstring: Return the first item of a sequence.
docstring_summary: Return the first item of a sequence.
docstring_tokens: Return the first item of a sequence .
function: def do_first(environment, seq):
      """Return the first item of a sequence."""
      try:
          return next(iter(seq))
      except StopIteration:
          return environment.undefined('No first item, sequence was empty.')
function_tokens: def do_first ( environment , seq ) : try : return next ( iter ( seq ) ) except StopIteration : return environment . undefined ( 'No first item, sequence was empty.' )