From type/QuantHash

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method Baggy(--> Baggy:D)

Coerce the QuantHash object to the equivalent object that uses the Baggy role. Note that for Mixy type coercion items with negative values will be skipped.

my %s is Set = <one two>;
say %s.Baggy; # OUTPUT: «Bag(one two)␤» 
my %m is Mix = one => 1, minus => -1;
say %m.Baggy; # OUTPUT: «Bag(one)␤»