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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def set_default_cc(self, arch_name, cc_cls):
 """ Set the default calling convention used for this library under a given architecture :param arch_name: The string name of the architecture, i.e. the ``.name`` field from archinfo. :parm cc_cls: The SimCC class (not an instance!) to use """

        arch_name = archinfo.arch_from_id(arch_name).name
        self.default_ccs[arch_name] = cc_cls