CODE EXAMPLE FOR PYTHON

dynamo python templete

import clr

clr.AddReference('RevitAPI')
from Autodesk.Revit.DB import *
from Autodesk.Revit.DB.Structure import *

clr.AddReference('RevitAPIUI')
from Autodesk.Revit.UI import *

clr.AddReference('System')
from System.Collections.Generic import List

clr.AddReference('RevitNodes')
import Revit
clr.ImportExtensions(Revit.GeometryConversion)
clr.ImportExtensions(Revit.Elements)

clr.AddReference('RevitServices')
import RevitServices
from RevitServices.Persistence import DocumentManager
from RevitServices.Transactions import TransactionManager

import System 
from System.Collections.Generic import *

import sys
sys.path.append(r'C:Program Files (x86)IronPython 2.7Lib')

doc = DocumentManager.Instance.CurrentDBDocument
uidoc=DocumentManager.Instance.CurrentUIApplication.ActiveUIDocument
uiapp = DocumentManager.Instance.CurrentUIApplication
app = DocumentManager.Instance.CurrentUIApplication.Application

def tolist(obj1):
	if hasattr(obj1,'__iter__') : return obj1
	else : return [obj1]
def flatten(x):
    result = []
    for el in x:
        if hasattr(el, "__iter__") and not isinstance(el, basestring):
            result.extend(flatten(el))
        else:
            result.append(el)
    return result
#Preparing input from dynamo to revit
element = UnwrapElement(tolist(IN[0]))

#Do some action in a Transaction
TransactionManager.Instance.EnsureInTransaction(doc)
#Do Action
TransactionManager.Instance.TransactionTaskDone()

OUT = element