We can see from the trace that the exception is thrown while examining the attribute data_format
. According to the doc, that parameter is supposed to be a string
with value either channels_last
or channels_first
. Instead, you have a Python tuple
and tuples don’t implement a function lower
, hence the error. NOTE: if data_format
is a string, the very next line checks the value, and throws an exception if it isn’t either channels_first
or channels_last
.
FWIW, that tuple looks suspiciously like an input_shape
. In the above Conv2D
doc look for the part that says When using this layer as the first layer in a model, provide the keyword argument input_shape
(tuple of integers…
Or take a quick peek at the Sequential model doc here
and look for the part that starts… A simple alternative is to just pass an input_shape
argument to your first layer:
I have now added content covering this to my Tips for troubles with Sequential and Functional API syntax thread