code: def find_single_file_project(self):  # type: () -> List[str]
          
          # TODO: use package_dirs
          packaged_dirs = ""
          try:
              # Right now only returns 1st.
              packaged_dirs = self.extract_package_dir()
          except:
              pass
          likely_src_folders = [".", "src/"]
          if packaged_dirs:
              likely_src_folders.append(packaged_dirs)
  
          candidates = []
          for likely_src in likely_src_folders:
              if not os.path.isdir(likely_src):
                  continue
              files = [f for f in os.listdir(likely_src) if os.path.isfile(f)]
  
              # BUG: doesn't deal with src/foo/bar.py
              for file in files:
                  if file.endswith("setup.py") or file == "setup":
                      continue  # duh
                  if file.endswith(".py"):
                      candidate = file.replace(".py", "")
                      if candidate != "setup":
                          candidates.append(candidate)
                  else:
                      if self.file_opener.is_python_inside(file):
                          candidates.append(file)
          return candidates
docs: Take first non-setup.py python file. What a mess.
          :return: