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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 GetConfiguredUsers(self):
 """Retrieve the list of configured Google user accounts. Returns: list, the username strings of users congfigured by Google. """

    if os.path.exists(self.google_users_file):
      users = open(self.google_users_file).readlines()
    else:
      users = []
    return [user.strip() for user in users]