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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 ReadRemoteFile(remote_file_path, hostname, ssh_key):
 """ Reads a remote file into a string. """

  cmd = 'sudo cat %s' % remote_file_path
  exit_code, output = RunCommandOnHost(cmd, hostname, ssh_key)
  if exit_code:
    raise IOError('Can not read remote path: %s' % (remote_file_path))
  return output