pycoin is probably your best bet. You need the utxo first, which you'll need to look up somewhere (blockchain.info is fine). Once you have the utxos, they'd need to be TxIns like this:
tx_in = TxIn("<utxo hash in binary here>", <utxo position, usually between 0 and 5>)
script = standard_tx_out_script(address)
tx_out = TxOut(<btc amount to send - fee>, script)
tx = Tx(1, [tx_in], [tx_out])
lookup = <this part you have to figure out>
tx.sign(lookup)
print tx.as_hex()
You can take the results and paste to something like blockchain.info's send transaction page.
NOTE: It's very easy to screw this up and have a too-high tx fee or lose your coins altogether. I would NOT recommend it. Install Armory and import the key or do the same using Mycelium. It's a lot safer to do it that way.