pelican blog post not getting generated

Question

I am trying to post to my pelican blog from another python app, so I am not doing pelican ./output -s settings.py from the commandline.

I have modified pelican to accept mocked argparse like object to pass what it needs, so I have moved the content of the main function in __init__.py

to function named runPelican(args) that accepts args, and from my app that has mocked Argparse like this,

class MockArgparse(object):
    """Mock for argparse's to pass to pelican
    """
    def __init__(self, verbosity=True, theme=None, output=None, path=None, delete_outputdir=None, 
                settings=None, ignore_cache=None, cache_path=None, selected_paths=None, autoreload=None):
        """
            Args:
                path (str): content path
                settings(str): settings python file path
        """
        super(MockArgparse, self).__init__()
        self.theme = theme
        self.cache_path = cache_path
        self.ignore_cache = ignore_cache
        self.delete_outputdir = delete_outputdir
        self.settings = settings
        self.output = output
        self.verbosity = verbosity
        self.autoreload = autoreload
        self.path = path
        self.selected_paths = selected_paths

I am calling the runPelican from my python app like this:

if make_entry(args):
    import pelican
    arg = MockArgparse(path=CONTENT_PATH, theme=THEME_PATH, output=OUTPUT_PATH, settings=SETTINGS_PATH)
    pelican.runPelican(arg)

Everything seems to go fine but the blog posts are not generated and Only error I am getting is

CRITICAL: SimplerXMLGenerator instance has no attribute '_write'

any help would be greatly appreciated.