xml.parsers.expat.ExpatError: XML or text declaration not at start of entity: line 5, column 0

[MuhammedEminK]

from wordpress_xmlrpc import Client ,WordPressPost
from wordpress_xmlrpc.methods.posts import EditPost, GetPost, GetPosts, NewPost
from wordpress_xmlrpc.methods.users import GetUserInfo

wp = Client("https://tik*****************/xmlrpc.php","t**********","**********")

wp.call(GetPosts())
wp.call(GetUserInfo())

post = WordPressPost()
t = "eklenti deneme"
a = """[python file="a.py"]"""
post.title = t
post.content = a
post.terms_names = {
"post_tag": ["test","Firstpost"],
"category": ["Introductions","Tests"]
}
sa = 1810
wp.call(EditPost(sa,post))

The code that worked 2 days ago is now giving an error, I couldn't find anywhere how to solve it. Can you help me?