code: def import_module(module_name):
      
      if import_path != sys.path:
          # Such a kludge. Only restrict imports if the `import_path` has
          # been changed. We don't want to always restrict imports, since
          # providing a path to `imp.find_module` stops it from searching
          # in special locations for built ins or frozen modules.
          #
          # The problem here is that this relies on the `sys.path` not being
          # independently changed since the initialization of this module.
          # If it is changed, then some packages may fail.
          #
          # Any other options available?
  
          # Raises an exception if the parent module cannot be imported.
          # This hopefully ensures that we only explicitly import modules
          # contained in `pydoc.import_path`.
          imp.find_module(module_name.split('.')[0], import_path)
  
      if module_name in sys.modules:
          return sys.modules[module_name]
      else:
          __import__(module_name)
          return sys.modules[module_name]
docs: Imports a module. A single point of truth for importing modules to
      be documented by `pydoc`. In particular, it makes sure that the top
      module in `module_name` can be imported by using only the paths in
      `pydoc.import_path`.
  
      If a module has already been imported, then its corresponding entry
      in `sys.modules` is returned. This means that modules that have
      changed on disk cannot be re-imported in the same process and have
      its documentation updated.