Batch posting on blogger using gdata python client
I would recommend using Google Blog converters instead ( https://code.google.com/archive/p/google-blog-converters-appengine/ )
To get started you will have to go through
https://github.com/google/gdata-python-client/blob/master/INSTALL.txt - Steps for setting up Google GData API https://github.com/pra85/google-blog-converters-appengine/blob/master/README.txt - Steps for using Blog Convertors
Once you have everything setup , you would have to run the following command (its the LiveJournal Username and password)
livejournal2blogger.sh -u <username> -p <password> [-s <server>]
Redirect its output into a .xml file. This file can now be imported into a Blogger blog directly by going to Blogger Dashboard , your blog > Settings > Other > Blog tools > Import Blog
Here remember to check the Automatically publish all imported posts and pages option. I have tried this once before with a blog with over 400 posts and Blogger did successfully import & published them without issue
Incase you have doubts the Blogger might have some issues (because the number of posts is quite high) or you have other Blogger blogs in your account. Then just for precaution sake , create a separate Blogger (Google) account and then try importing the posts. After that you can transfer the admin controls to your real Blogger account (To transfer , you will first have to send an author invite , then raise your real Blogger account to admin level and lastly remove the dummy account. Option for sending invite is present at Settings > Basic > Permissions > Blog Authors )
Also make sure that you are using Python 2.5 otherwise these scripts will not run. Before running livejournal2blogger.sh , change the following line (Thanks for Michael Fleet for this fix http://michael.f1337.us/2011/12/28/google-blog-converters-blogger2wordpress/ )
PYTHONPATH=${PROJ_DIR}/lib python ${PROJ_DIR}/src/livejournal2blogger/lj2b.py $*
to
PYTHONPATH=${PROJ_DIR}/lib python2.5 ${PROJ_DIR}/src/livejournal2blogger/lj2b.py $*
P.S. I am aware this is not the answer to your question but as the objective of this answer is same as your question (To import more than 50 posts in a day) , Thats why I shared it. I don't have much knowledge of Python or GData API , I setup the environment & followed these steps to answer this question (And I was able to import posts from LiveJournal to Blogger with it ).
# build feed
request_feed = gdata.base.GBaseItemFeed(atom_id=atom.Id(text='test batch'))
# format each object
entry1 = gdata.base.GBaseItemFromString('--XML for your new item goes here--')
entry1.title.text = 'first batch request item'
entry2 = gdata.base.GBaseItemFromString('--XML for your new item here--')
entry2.title.text = 'second batch request item'
# Add each blog item to the request feed
request_feed.AddInsert(entry1)
request_feed.AddInsert(entry2)
# Execute the batch processes through the request_feed (all items)
result_feed = gd_client.ExecuteBatch(request_feed)