code: def find_providers():
      
      providers_list = sorted({modname for (_, modname, _)
                               in pkgutil.iter_modules(providers.__path__)
                               if modname != 'base'})
  
      try:
          distribution = pkg_resources.get_distribution('dns-lexicon')
      except pkg_resources.DistributionNotFound:
          return {provider: True for provider in providers_list}
      else:
          return {provider: _resolve_requirements(provider, distribution)
                  for provider in providers_list}
docs: Find all providers registered in Lexicon, and their availability