Getting Assert Error on every PDF

[sof123]

Hey just trying to get started with slate using the tutorial and getting this error. I've tried with 3 pdfs now. Just running the basic code from the tutorial:

import slate with open('testpdf3.pdf') as f: print type(f) doc = slate.PDF(f)

And the stack trace:

Traceback (most recent call last):
File "test.py", line 7, in
doc = slate.PDF(f)
File "C:\Users\S\Anaconda2\lib\site-packages\slate\slate.py", line 38, in init
self.doc.set_parser(self.parser)
File "C:\Users\S\Anaconda2\lib\site-packages\pdfminer\pdfparser.py", line 318, in set_parser
self.xrefs = parser.read_xref()
File "C:\Users\S\Anaconda2\lib\site-packages\pdfminer\pdfparser.py", line 747, in read_xref
self.read_xref_from(pos, xrefs)
File "C:\Users\S\Anaconda2\lib\site-packages\pdfminer\pdfparser.py", line 727, in read_xref_from
xref.load(self, debug=self.debug)
File "C:\Users\S\Anaconda2\lib\site-packages\pdfminer\pdfparser.py", line 99, in load
self.load_trailer(parser)
File "C:\Users\S\Anaconda2\lib\site-packages\pdfminer\pdfparser.py", line 107, in load_trailer
assert kwd is self.KEYWORD_TRAILER
AssertionError

I've tried printing kwd and it's always an integer while KEYWORD_TRAILER is 'trailer'
Used this command to install:

pip install --upgrade --ignore-installed slate==0.3 pdfminer==20110515

I'm on Windows, Python 2.7.12

[TG0]

Try:

with open('testpdf3.pdf', 'rb') as f: