Bug in BOW_text_classifaction.ipynb

1)In  MAX_LEN you declared  MAX_LEN ="128" which is a string and when you are passing it into function it is causing an error .So try to remove hyphens in it. and make  MAX_LEN=128


`
# Set parameters

MAX_LEN = "256" #@param [64, 256, 512, 1024] {allow-input: true}
MAX_VOCAB = 1000 #@param [1000, 5000, 10000, 100000] {allow-input: true}

`