def fetch_public_key(repo):
keyurl = '<STR_LIT>'.format(repo)<EOL>data = json.loads(urlopen(keyurl).read().decode())<EOL>if '<STR_LIT:key>' not in data:<EOL><INDENT>errmsg = "<STR_LIT>".format(repo)<EOL>errmsg += "<STR_LIT>"<EOL>raise ValueError(errmsg)<EOL><DEDENT>return data['<STR_LIT:key>']<EOL>
Download RSA public key Travis will use for this repo.

    Travis API docs: http://docs.travis-ci.com/api/#repository-keys