code: def _import_module(name, package='vlfd', warn=True, prefix='_py_', ignore='_'):
      
      import warnings
      from importlib import import_module
      try:
          try:
              module = import_module(name)
          except ImportError:
              module = import_module('.' + name, package=package)
      except ImportError:
          if warn:
              warnings.warn("failed to import module %s" % name)
      else:
          for attr in dir(module):
              if ignore and attr.startswith(ignore):
                  continue
              if prefix:
                  if attr in globals():
                      globals()[prefix + attr] = globals()[attr]
                  elif warn:
                      warnings.warn("no Python implementation of " + attr)
              globals()[attr] = getattr(module, attr)
          return True
docs: Try import all public attributes from module into global namespace.
  
      Existing attributes with name clashes are renamed with prefix.
      Attributes starting with underscore are ignored by default.
  
      Return True on successful import.