pyobfuscate throw Error if 'None' found inside lambda

[pooja-zakhariya]

Hello,

I am trying pyobfuscate for encrypting my file. File contains below code piece in which pyobfuscate raise error:
File "/usr/bin/pyobfuscate", line 841, in parse
raise RuntimeError("Overlooked symbol '%s' on line %d column %d" % (t_string, srow, scol))
RuntimeError: Overlooked symbol 'None' on line 51 column 39

Code:
'name': lambda self,cr,uid,ctx=None: '/'

Waiting for reply.
Thank You