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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 create(self, vrf_name, rd=None):
 """ Creates a new VRF resource Note: A valid RD has the following format admin_ID:local_assignment. The admin_ID can be an AS number or globally assigned IPv4 address. The local_assignment can be an integer between 0-65,535 if the admin_ID is an IPv4 address and can be between 0-4,294,967,295 if the admin_ID is an AS number. If the admin_ID is an AS number the local_assignment could also be in the form of an IPv4 address. Args: vrf_name (str):
 The VRF name to create rd (str):
 The value to configure the vrf rd Returns: True if create was successful otherwise False """

        commands = ['vrf definition %s' % vrf_name]
        if rd:
            commands.append('rd %s' % rd)
        return self.configure(commands)