text: """Diagnostic functions, mainly for use when doing tech support."""
  
  __license__ = "MIT"
  
  import cProfile
  from StringIO import StringIO
  from HTMLParser import HTMLParser
  import argeweb.libs.bs4
  from argeweb.libs.bs4 import BeautifulSoup, __version__
  from argeweb.libs.bs4.builder import builder_registry
  
  import os
  import pstats
  import random
  import tempfile
  import time
  import traceback
  import sys
  import cProfile
  
  def diagnose(data):
      """Diagnostic suite for isolating common problems."""
      print "Diagnostic running on Beautiful Soup %s" % __version__
      print "Python version %s" % sys.version
  
      basic_parsers = ["html.parser", "html5lib", "lxml"]
      for name in basic_parsers:
          for builder in builder_registry.builders:
              if name in builder.features:
                  break
          else:
              basic_parsers.remove(name)
              print (
                  "I noticed that %s is not installed. Installing it may help." %
                  name)
  
      if 'lxml' in basic_parsers:
          basic_parsers.append(["lxml", "xml"])
          try:
              from lxml import etree
              print "Found lxml version %s" % ".".join(map(str,etree.LXML_VERSION))
          except ImportError, e:
              print (
                  "lxml is not installed or couldn't be imported.")
  
  
      if 'html5lib' in basic_parsers:
          try:
              import html5lib
              print "Found html5lib version %s" % html5lib.__version__
          except ImportError, e:
              print (
                  "html5lib is not installed or couldn't be imported.")
  
      if hasattr(data, 'read'):
          data = data.read()
      elif os.path.exists(data):
          print '"%s" looks like a filename. Reading data from the file.' % data
          data = open(data).read()
      elif data.startswith("http:") or data.startswith("https:"):
          print '"%s" looks like a URL. Beautiful Soup is not an HTTP client.' % data
          print "You need to use some other library to get the document behind the URL, and feed that document to Beautiful Soup."
          return
      print
  
      for parser in basic_parsers:
          print "Trying to parse your markup with %s" % parser
          success = False
          try:
              soup = BeautifulSoup(data, parser)
              success = True
          except Exception, e:
              print "%s could not parse the markup." % parser
              traceback.print_exc()
          if success:
              print "Here's what %s did with the markup:" % parser
              print soup.prettify()
  
          print "-" * 80
  
  def lxml_trace(data, html=True, **kwargs):
      """Print out the lxml events that occur during parsing.
  
      This lets you see how lxml parses a document when no Beautiful
      Soup code is running.
      """
      from lxml import etree
      for event, element in etree.iterparse(StringIO(data), html=html, **kwargs):
          print("%s, %4s, %s" % (event, element.tag, element.text))
  
  class AnnouncingParser(HTMLParser):
      """Announces HTMLParser parse events, without doing anything else."""
  
      def _p(self, s):
          print(s)
  
      def handle_starttag(self, name, attrs):
          self._p("%s START" % name)
  
      def handle_endtag(self, name):
          self._p("%s END" % name)
  
      def handle_data(self, data):
          self._p("%s DATA" % data)
  
      def handle_charref(self, name):
          self._p("%s CHARREF" % name)
  
      def handle_entityref(self, name):
          self._p("%s ENTITYREF" % name)
  
      def handle_comment(self, data):
          self._p("%s COMMENT" % data)
  
      def handle_decl(self, data):
          self._p("%s DECL" % data)
  
      def unknown_decl(self, data):
          self._p("%s UNKNOWN-DECL" % data)
  
      def handle_pi(self, data):
          self._p("%s PI" % data)
  
  def htmlparser_trace(data):
      """Print out the HTMLParser events that occur during parsing.
  
      This lets you see how HTMLParser parses a document when no
      Beautiful Soup code is running.
      """
      parser = AnnouncingParser()
      parser.feed(data)
  
  _vowels = "aeiou"
  _consonants = "bcdfghjklmnpqrstvwxyz"
  
  def rword(length=5):
      "Generate a random word-like string."
      s = ''
      for i in range(length):
          if i % 2 == 0:
              t = _consonants
          else:
              t = _vowels
          s += random.choice(t)
      return s
  
  def rsentence(length=4):
      "Generate a random sentence-like string."
      return " ".join(rword(random.randint(4,9)) for i in range(length))
          
  def rdoc(num_elements=1000):
      """Randomly generate an invalid HTML document."""
      tag_names = ['p', 'div', 'span', 'i', 'b', 'script', 'table']
      elements = []
      for i in range(num_elements):
          choice = random.randint(0,3)
          if choice == 0:
              # New tag.
              tag_name = random.choice(tag_names)
              elements.append("<%s>" % tag_name)
          elif choice == 1:
              elements.append(rsentence(random.randint(1,4)))
          elif choice == 2:
              # Close a tag.
              tag_name = random.choice(tag_names)
              elements.append("</%s>" % tag_name)
      return "<html>" + "\n".join(elements) + "</html>"
  
  def benchmark_parsers(num_elements=100000):
      """Very basic head-to-head performance benchmark."""
      print "Comparative parser benchmark on Beautiful Soup %s" % __version__
      data = rdoc(num_elements)
      print "Generated a large invalid HTML document (%d bytes)." % len(data)
      
      for parser in ["lxml", ["lxml", "html"], "html5lib", "html.parser"]:
          success = False
          try:
              a = time.time()
              soup = BeautifulSoup(data, parser)
              b = time.time()
              success = True
          except Exception, e:
              print "%s could not parse the markup." % parser
              traceback.print_exc()
          if success:
              print "BS4+%s parsed the markup in %.2fs." % (parser, b-a)
  
      from lxml import etree
      a = time.time()
      etree.HTML(data)
      b = time.time()
      print "Raw lxml parsed the markup in %.2fs." % (b-a)
  
      import html5lib
      parser = html5lib.HTMLParser()
      a = time.time()
      parser.parse(data)
      b = time.time()
      print "Raw html5lib parsed the markup in %.2fs." % (b-a)
  
  def profile(num_elements=100000, parser="lxml"):
  
      filehandle = tempfile.NamedTemporaryFile()
      filename = filehandle.name
  
      data = rdoc(num_elements)
      vars = dict(bs4=bs4, data=data, parser=parser)
      cProfile.runctx('bs4.BeautifulSoup(data, parser)' , vars, vars, filename)
  
      stats = pstats.Stats(filename)
      # stats.strip_dirs()
      stats.sort_stats("cumulative")
      stats.print_stats('_html5lib|bs4', 50)
  
  if __name__ == '__main__':
      diagnose(sys.stdin.read())