code: def guess_lexer(_text, **options):
      """Guess a lexer by strong distinctions in the text (eg, shebang)."""
  
      # try to get a vim modeline first
      ft = get_filetype_from_buffer(_text)
  
      if ft is not None:
          try:
              return get_lexer_by_name(ft, **options)
          except ClassNotFound:
              pass
  
      best_lexer = [0.0, None]
      for lexer in _iter_lexerclasses():
          rv = lexer.analyse_text(_text)
          if rv == 1.0:
              return lexer(**options)
          if rv > best_lexer[0]:
              best_lexer[:] = (rv, lexer)
      if not best_lexer[0] or best_lexer[1] is None:
          raise ClassNotFound("no lexer matching the text found")
      return best_lexer[1](**options)
  
imports: import re
  import sys
  import types
  import fnmatch
  from os.path import basename
  from pygments.lexers._mapping import LEXERS
  from pygments.modeline import get_filetype_from_buffer
  from pygments.plugin import find_plugin_lexers
  from pygments.util import ClassNotFound, itervalues, guess_decode
label_desc: Use image node_id 13 for calling a global function with example usage: guess_lexer(_text) and returns: best_lexer, get_lexer_by_name, lexer