single and multiline python expression in Nuke

nuke_py_expressions.py

#multiline py nuke's expression
b = nuke.nodes.Blur()
kb = b.knob('size')
multiline_python_expr = '''
[python -execlocal {
def myFunction(x):
    return x*2
t = nuke.frame()
x = myFunction(t)
ret = x
}]'''
kb.setExpression( multiline_python_expr )
b.knob('label').setValue('multiline')


#single line py nuke's expression
b = nuke.nodes.Blur()
kb = b.knob('size')
singleline_py_expr = """ [python nuke.frame()/10 ]""" 
kb.setExpression( singleline_py_expr )
b.knob('label').setValue('single line')