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{
  'UTC' => 0,
  # ISO 8601
  'Z' => 0,
  # RFC 822
  'UT' => 0, 'GMT' => 0,
  'EST' => -5, 'EDT' => -4,
  'CST' => -6, 'CDT' => -5,
  'MST' => -7, 'MDT' => -6,
  'PST' => -8, 'PDT' => -7,
  # Following definition of military zones is original one.
  # See RFC 1123 and RFC 2822 for the error in RFC 822.
  'A' => +1, 'B' => +2, 'C' => +3, 'D' => +4,  'E' => +5,  'F' => +6, 
  'G' => +7, 'H' => +8, 'I' => +9, 'K' => +10, 'L' => +11, 'M' => +12,
  'N' => -1, 'O' => -2, 'P' => -3, 'Q' => -4,  'R' => -5,  'S' => -6, 
  'T' => -7, 'U' => -8, 'V' => -9, 'W' => -10, 'X' => -11, 'Y' => -12,
}