allow call on validator instances
allow call on validator instances
nicolaiarocci/cerberus,funkyfuture/cerberus,MacHu-GWU/cerberus-sanhe,nicolaiarocci/cerberus,calve/cerberus,brettatoms/cerberus,calve/cerberus,dkellner/cerberus,dkellner/cerberus,MacHu-GWU/cerberus-sanhe,pyeve/cerberus,pyeve/cerberus,funkyfuture/cerberus