Error while Fetching Hash value for a block chain - python-3.6

Question

I am working on a sample blockchain implementation with dummy data. I have One method is createGenesisBlock() for creating first block and other method is Makeblock() for blockchain. The code is written in python 3.6
I am facing issue with Makeblock when retrieving the Hash Value created in Genesis Block and stored in a text file.
Below is the error Message :
parentHash=parentBlock[u'hash']
TypeError: string indices must be integers
Code Snippet are below :
*def makeBlock(self,txns, parentBlock):
parentBlock=parentBlock.strip(parentBlock[0])
parentblocklen=len(parentBlock)
parentBlock=parentBlock.strip(parentBlock[parentblocklen-1])
parentHash=parentBlock[u'hash']
blockNumber = parentBlock[u'contents'][u'blockNumber'] + 1
blockContents = {u'blockNumber': blockNumber, u'parentHash': parentHash, u'RCount': len(txns), 'records': txns}
blockHash = hashMe(blockContents)
block = {u'hash': blockHash, u'contents': blockContents}
return block*
Above, method makeBlock() is taking below string as 2nd argument . But while fetching the hash from the below string is resulting in error.
************string starts*********
{'hash': 'af12f6148f5d328d1272e81393f199a6', 'contents': {'blockNumber': 0, 'parentHash': None, 'RCount': 2, 'records': [{'Patient ID': (b'\xa6\xe0<"\x18\x18F~-.g\x1cX\xf3\r\x86\xc0\x04hUG\xa7PT\xa2\x85\'\x06S?\xab3\xf4T$I\xcf\x94\xcc \xc8\x1b\xfb\xfe\nTw!\x80q\x1ae1\x99\x9e\xbf\xbc^D\xea\xe9X\x06\x8f\x8es\xb3\x02sAdf07\xdc\xdd\xf0\x17M\xf5\xeep\xbd\xeb\x88V\xd6\x86\xd4\9e\xcf\x93\x06p\xc4\x1a\xe8\r\xc5\xa2\xd6j\xc4\xff\xc7\xfb\x81\xfaa_\xe0C\x97#f3Zu7\xb2\x07YO\xe3',), 'Insurance ID': (b'\xaa\x1bJ\x84z\xe9\r\x8e\`IC\x9f\xf9\x03\xf4\xf5/\x1ceXW\x01\xf3\x03\r~yTi\xff:\xa3\x05\xcf\x84xl\xf9r\x95C\xc1f\xe6\xec\xbc\tz\xa9\xd0J\xe6#\xe6\xc5\xf8\xbb\xb1\x05flY\xc6\xa3\xfdy+\xa2Eq\xbb\xebe\x8dm?404T\xe9\xb2\x85_\x89\xc4&\xa2<\xac\xbf\xc2\xd8z\xee\x9e\xd2\xfc\xf8\xa2<.(i\x07\x10o\x9f\xf9\xa9\x1bH\xda\xd4?\xd9\x7f\xb4G\xeb\x15\x13\xbaW\x9b\r\xc3',), 'DOS': "'19-09-2216'", 'Claim Amount': "'2280.00'", 'Claim ID': "'9348'", 'Provider ID': (b'q\x8a!\xfce\xb7\x8e\xeax\x8a\xc9h\xd4\\x02P\xb5j\xdc\xb2\xe5\xa4\xc6#\xbd\xda\x1e,;)\x83\xe7\x98\x15\xe2\xe7\xe4c\xd5\x9e\x99k\x8a\x97\xdd#\x803\xc0\xbbY3\xa7\xfe\xeb&\x0f\xa3/\x1e\x96\xdf}\x83\x00euX\xd4J\r\xd1\xd91\xb3\x89\xc9I\x94L\xf2U3L=\xb2\xa9+43\x95t^\x9a\x85\x02\xea\x16V\xac\xad\xbc"=.i\xab8?7\x1di\x83\x18\xee\x9aM\xae\x84\xf8p\x9ae\xf9\xb0\x82',), 'URL': "'www.yahoo.com'"}, {'Patient ID': (b'\xbf\xec\rk\xaa\x99\xde\t\xfe\xf7R\x0fu6\x0fz\x9e\x01\xa6\xbb\x80\xfeyh\xe7\n\xeb\x03H\x01/ \xfc\xda\x8dH\xc9\x12R\xe1.E\xc3\xb1,\x0b)\x7f\xca\xc73"\xa8\x0c{\xe4Q\x95pi\x97\xfaN\xc3^\xd3\xf1\x0buK\xe3c\x06\xd1\xfe\xa6\xdd\xafO\xfe#\x17\xe9\xe6\xd6\xe1\xb3s#{\x9fV\xba\x13\xae\xa7q\x8b\x08\x9b\xb1\xa0\x0eA\xf3M\x96\xf6\xbbhs[\xbd/Z:\x87Y\xe8\xb9\xe0\xcb\xbb\xfb\x0b\x1d#\xb0',), 'Insurance ID': (b'\x06\x11\xaa\x08\xde9\xbcd\x91\xe28\xd6J[\xf6\x1a\xbb{\xc9f\x8aa\xdd\x86\xbf\x17\xdf\xaaQiZq\x91\xbb\xf1F\x1f[n0i\xc1\x96\xf2\x9f\xf1.\xde\x11P\xb7\xcd\x0e\xab\x97\xd3W\xa6\xd0\xc0\xc7\xbe\xb7\x8a\xd2\xe9\x84\x9bM\xeb\x0e\x8f\x91\t\xd9\xecq\xad\xd8w\r\xc4\x08\x0f\xa5\x99\xc3)\xa7\x8b\xa0\xa5\xc6\xbf\xce\xfa\xe6\x9f9\x81)\xfevJ\xad\x1d\xc9%\xe0\xe1(\xd5\xd7\x19g\x1f\xe1{\x1c\x1e%\x10 \x12\xc6\x03\xce',), 'DOS': "'10-11-2012'", 'Claim Amount': "'1230.00'", 'Claim ID': "'98009'", 'Provider ID': (b'\x81/O\xddKPk6XD\x82g\x97\x80\x87\x92\xc5\xfa\x07v \xf9\xe43\xd9\x00z\xf8\xe9\x1e3"\xa1\xeb\x039\xda\t:K\r\xda\xbcx\x84\x95\xdf\xa2\xe9\xdcU\xd9\C41\xb7\xf0\x07\xf5euy\xd3Ab\x10teE\xf2\xf2\x10\xc0\x1c\x16$V7\xf1\x8d\x16\x8a\x14\x02\x16\xff\xe3\xad\xa3#`\x13\xd0\xef\x18\x83\x13D\x91\x05>\x13\x8aY\xdb\xfeN\x99\xef\x9d>\xc9\xf2\xfbMj\xd1\x00E\xd5\xdaYW\x1d\x0e\xca\xa0',), 'URL': "'www.oracle.com'"}]}}*
************string ends *********
NOTE: Surprizingly excuting the same on python shell. I am able to fetch parentHash value into any variable.
parentHash=parentBlock[u'hash'] (executing on shell returns the hash value successfully: af12f6148f5d328d1272e81393f199a6)
parentHash=parentBlock[u'hash'] (executing via python script is resulting in ERROR (TypeError: string indices must be integers)
Could someone please help where is the issue and why the same code works fine in python shell but throws a error in Method while executing?