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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 set_vrf(self, name, vrf, default=False, disable=False):
 """Applies a VRF to the interface Note: VRF being applied to interface must already exist in switch config. Ethernet port must be in routed mode. This functionality can also be handled in the VRF api. Args: name (str):
 The interface identifier. It must be a full interface name (ie Ethernet, not Et) vrf (str):
 The vrf name to be applied to the interface default (bool):
 Specifies the default value for VRF disable (bool):
 Specifies to disable VRF Returns: True if the operation succeeds otherwise False is returned """

        commands = ['interface %s' % name]
        commands.append(self.command_builder('vrf forwarding', vrf,
                                             default=default, disable=disable))
        return self.configure(commands)