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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 get_create_vlan(self, nexus_host, vlanid, vni, conf_str):
 """Returns an XML snippet for create VLAN on a Nexus Switch."""


        starttime = time.time()

        if vni:
            body_snip = snipp.BODY_VXLAN_ALL_INCR % (vlanid, vni)
        else:
            body_snip = snipp.BODY_VLAN_ALL_INCR % vlanid
        conf_str += body_snip + snipp.BODY_VLAN_ALL_CONT

        self.capture_and_print_timeshot(
            starttime, "get_create_vlan",
            switch=nexus_host)

        return conf_str