Tracking package dependencies

def pkg_tracking(self):
        """Tracking package dependencies
        """
        flag = []
        options = [
            "-t",
            "--tracking"
        ]
        additional_options = [
            "--check-deps",
            "--graph=",
            "--case-ins"
        ]
        for arg in self.args[2:]:
            if arg.startswith(additional_options[1]):
                flag.append(arg)
                self.args.remove(arg)
            if arg in additional_options:
                flag.append(arg)
        # clean additional options from args
        for f in flag:
            if f in self.args:
                self.args.remove(f)
        # print usage message if wrong additional option
        for arg in self.args:
            if arg.startswith("--"):
                if arg not in additional_options:
                    usage("")
                    raise SystemExit()
        if (len(self.args) >= 3 and len(self.args) <= 3 and
                self.args[0] in options and
                self.args[1] in self.meta.repositories):
            TrackingDeps(self.args[2], self.args[1], flag).run()
        elif (len(self.args) >= 2 and
                self.args[1] not in self.meta.repositories):
            usage(self.args[1])
        else:
            usage("")