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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _ensure_module_folder_exists():
 """ Checks to see if the module folder exists. If it does not, create it. If there is an existing file with the same name, we raise a RuntimeError. """

  if not os.path.isdir(MODULES_FOLDER_PATH):
    try:
      os.mkdir(MODULES_FOLDER_PATH)
    except OSError, e:
      if "file already exists" in str(e):
        raise RuntimeError("Could not create modules folder: file exists with the same name")