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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 _validate_generic_parameters(self, args):
 """Validate the generic request parameters. @param args: Parsed schema arguments. @raises APIError: In the following cases: - Action is not included in C{self.actions} - SignatureVersion is not included in C{self.signature_versions} - Expires and Timestamp are present - Expires is before the current time - Timestamp is older than 15 minutes. """

        utc_now = self.get_utc_time()

        if getattr(self, "actions", None) is not None:
            # Check the deprecated 'actions' attribute
            if not args["action"] in self.actions:
                raise APIError(400, "InvalidAction", "The action %s is not "
                               "valid for this web service." % args["action"])
        else:
            self.registry.check(args["action"], args["version"])

        if not args["signature_version"] in self.signature_versions:
            raise APIError(403, "InvalidSignature", "SignatureVersion '%s' "
                           "not supported" % args["signature_version"])

        if args["expires"] and args["timestamp"]:
            raise APIError(400, "InvalidParameterCombination",
                           "The parameter Timestamp cannot be used with "
                           "the parameter Expires")
        if args["expires"] and args["expires"] < utc_now:
            raise APIError(400,
                           "RequestExpired",
                           "Request has expired. Expires date is %s" % (
                                args["expires"].strftime(self.time_format)))
        if (args["timestamp"]
            and args["timestamp"] + timedelta(minutes=15) < utc_now):
            raise APIError(400,
                           "RequestExpired",
                           "Request has expired. Timestamp date is %s" % (
                               args["timestamp"].strftime(self.time_format)))