Function try_map_vec 

pub fn try_map_vec<A, B: TryFrom<A>>(
    other: Vec<A>,
) -> Result<Vec<B>, <B as TryFrom<A>>::Error>

Convert a vector of A into a vector of B using TryFrom Useful to convert vectors of structs into protos, like Vec<IdentityUpdate> to Vec<IdentityUpdateProto> or vice-versa.