code: def find_cc(arch, args, sp_delta):
          
          if arch.name not in CC:
              return None
          possible_cc_classes = CC[arch.name]
          for cc_cls in possible_cc_classes:
              if cc_cls._match(arch, args, sp_delta):
                  return cc_cls(arch, args=args, sp_delta=sp_delta)
          return None
docs: Pinpoint the best-fit calling convention and return the corresponding SimCC instance, or None if no fit is
          found.
  
          :param Arch arch:       An ArchX instance. Can be obtained from archinfo.
          :param list args:       A list of arguments.
          :param int sp_delta:    The change of stack pointer before and after the call is made.
          :return:                A calling convention instance, or None if none of the SimCC subclasses seems to fit the
                                  arguments provided.
          :rtype:                 SimCC or None