A very similar topic was already discussed here:
building up from that example, all you need to do is use the “SaveAs” method of the family document:
Here’s the code:
import clr
clr.AddReference('ProtoGeometry')
from Autodesk.DesignScript.Geometry import *
clr.AddReference('RevitAPI')
import Autodesk
clr.AddReference('RevitServices')
import RevitServices
from RevitServices.Persistence import DocumentManager
from RevitServices.Transactions import TransactionManager
doc = DocumentManager.Instance.CurrentDBDocument
#Close all transactions
trans = TransactionManager.Instance
trans.ForceCloseTransaction()
fams = IN[0]
paths = IN[1]
#unwrap the Dynamo elements
fams = map(UnwrapElement, fams)
for i in xrange(len(fams) ):
famDoc = doc.EditFamily(fams[i])
famDoc.SaveAs(paths[i])
famDoc.Close(False)
OUT = 0