Pyhton script error -IndentationError: unexpected inden

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EuStockMarkets_NA
ADO.NET: Python script error.
 File "PythonScriptWrapper.PY", line 9
 completedData = dataset.fillna(method='backfill', inplace=False)
 ^
 IndentationError: unexpected inden

Python 3.7.3 (v3.7.3:ef4ec6ed12, Mar 25 2019, 21:26:53) [MSC v.1916 32 bit (Intel)] on win32
Type "help", "copyright", "credits" or "license" for more information.
>>> import sys
>>> print(sys.exec_prefix)
C:\Users\mudas\AppData\Local\Programs\Python\Python37-32
>>>

I was trying to complete this article on my windows 10 pro mahine and i got the above error .

https://docs.microsoft.com/en-us/power-bi/desktop-python-in-query-editor