utils.tenor_sort_key
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spice.utils.tenor_sort_key(tenor: str) -> int

   Generate sort key for tenor strings to enable chronological
   ordering.

   Parameters:
      **tenor** -- Tenor string (e.g., "3M", "1Y", "5Y", "10Y")

   Returns:
      Integer sort key in months (e.g., "3M" -> 3, "1Y" -> 12, "5Y" ->
      60) Unknown formats return 999999 to sort last

   -[ Example ]-

   >>> tenors = ["5Y", "3M", "1Y", "10Y"]
   >>> sorted(tenors, key=tenor_sort_key)
   ['3M', '1Y', '5Y', '10Y']
