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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 toPostArgs(self):
 """ Return all arguments with openid. in front of namespaced arguments. @return bytes """

        args = {}

        # Add namespace definitions to the output
        for ns_uri, alias in self.namespaces.items():
            if self.namespaces.isImplicit(ns_uri):
                continue
            if alias == NULL_NAMESPACE:
                ns_key = 'openid.ns'
            else:
                ns_key = 'openid.ns.' + alias
            args[ns_key] = oidutil.toUnicode(ns_uri)

        for (ns_uri, ns_key), value in self.args.items():
            key = self.getKey(ns_uri, ns_key)
            # Ensure the resulting value is an UTF-8 encoded *bytestring*.
            args[key] = oidutil.toUnicode(value)

        return args