Remove Empty Spaces with Field Calculator

[NickArcher]

Hi,

I have a fields that is populated with correct values, <Null>, and whitespace/empty. The field is of text value with both numbers and letters in the correct values. I want to remove all of the whitespace/empty and replace them with <Null> instead. I am trying to do this with the field calculator and python.

My current prelogic statement is:

def makeNull(unitType):
  if unitType == str():
    return None

And the box below is: 

makeNull( !UnitType!)

However when the field is calculated it turns all of the values to <Null> instead of just the whitespace/empty. Any Idea what I am doing wrong?

[IanMurray · Accepted solution]

Maybe you only try evaluating empty strings.

def makeNull(unitType):
  if unitType == "":
    return None
  else:
    return unitType‍‍‍‍‍‍‍‍‍‍

[DanPatterson_Retired]

#---- snag the fat-fingered space placer ---
a = "    "
a.strip() == ""
Out[9]: True‍‍‍‍

[NickArcher]

So the problem was I didn't have a else statement. I added in your else statement and it worked. Thanks.