I'm Trying to add a space between two concatenated field values

[OLANIYANOLAKUNLE]

I want to add a space between two concatenated field values that would appear like this "Kunle Street", I've tried the code below but its not giving me the expected result any suggestions? Thank you

arcpy.CalculateField_management("Street", "STREET_NAME", "!NAME!" + " " + "!NAME_EXTEN!", "PYTHON_9.3", "")

[T__WayneWhitley]

"'{} {}'.format(!NAME!, !NAME_EXTEN!)"

[markdenil · Accepted solution]

instead of
"!NAME!" + " " + "!NAME_EXTEN!",

try
"%s %s" % (!NAME!, !NAME_EXTEN!)

or
"!NAME! + ' ' + !NAME_EXTEN!"

[OLANIYANOLAKUNLE]

instead of
"!NAME!" + " " + "!NAME_EXTEN!",

try
"%s %s" % (!NAME!, !NAME_EXTEN!)

or
"!NAME! + ' ' + !NAME_EXTEN!"

Thanks worked like magic.....