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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 update_vlan(self, name, vid, vni):
 """Adds a new vlan to vni mapping for the interface EosVersion: 4.13.7M Args: vlan (str, int):
 The vlan id to map to the vni vni (str, int):
 The vni value to use Returns: True if the command completes successfully """

        cmd = 'vxlan vlan %s vni %s' % (vid, vni)
        return self.configure_interface(name, cmd)