This is the ValueSet that contains all the codes in TRUST.KEYUSAGE ValueSet of key usage codes (http://smart.who.int/trust/ValueSet/WHO.TRUST.KEYUSAGE) and TRUST.KEYUSAGE ValueSet of key usage codes (http://smart.who.int/trust/ValueSet/WHO.TRUST.KEYUSAGE). E.g. what you have to deal with if you get resources containing codes in either of them