Official TwoForOne Discussion

when I run:
$ openssl x509 -in key1.pem -text -noout

I get:
unable to load certificate. 139729726211392:error:0909006C:PEM routines:get_name:no start line:…/crypto/pem/pem_lib.c:745:Expecting: TRUSTED CERTIFICATE

Also, some common python modules fail to load these PEM files too. I was able to parse them with some other tools and get the necessary information, but I am wondering why the most common methods fail? Am I overlooking something silly? Can anyone kindly explain? I feel frustrated.
~Thanks!