Object does not appear to be a 8-bit string path or a Python file-like object

I'm not sure why you added the np.genfromtxt() call. The following lines to create the in-memory file object are enough; these are the last lines in the view function, starting at your png_output line:

png_output = io.BytesIO()canvas.print_png(png_output)response = make_response(png_output.getvalue())response.headers['Content-Type'] = 'image/png'return response

With those changes, the code produces a plot:

x_train=np.array(list(map(img_preprocess,x_train)))x_valid=np.array(list(map(img_preprocess,x_valid)))

bit shows object-does-not-appear-to-be-a-8-bit-string-path-or-a-python-file-like-object

This Error is because Here you already changed shape of x_train by executing x_train=np.array(list(map(img_preprocess,x_train))) this line, so x_train is updated now and again if you will give x_train as input to the x_train=np.array(list(map(img_preprocess,x_train))) function then it will give this error

solution: reset your python kernel and run all code in sequence again.

x_train=np.array(list(map(img_preprocess,x_train)))x_valid=np.array(list(map(img_preprocess,x_valid)))bit shows object-does-not-appear-to-be-a-8-bit-string-path-or-a-python-file-like-object

Whats's the problem behind it?