You're seeing just the function floatize_keys, go back to Cldr.Map module for more information.
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floatize_keys(map, options \\ [])

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Transforms a map's String.t keys to Float.t values.


The map key is converted to a float from a String.t only when the key is comprised of a valid float form.

Keys which cannot be converted to a float are returned unchanged.


iex> Cldr.Map.floatize_keys %{a: %{"1.0" => "value"}}
%{a: %{1.0 => "value"}}

iex> Cldr.Map.floatize_keys %{a: %{"1" => "value"}}
%{a: %{1.0 => "value"}}