api example of posting a file. The content file object is part of django but it's easily separated if you use python. Just copy that class out https://github.com/django/django/blob/master/django/core/files/base.py#L132

gistfile1.py

from django.core.files.base import ContentFile

        f = ContentFile(o.read(), name='pic.png')

        response = signed_post(self.api_client, self.c, '/api/v1/user/register/', {
            'social_id': 'twitter:123452',
            'gender': 'f',
            'email': '[email protected]',
            'name': 'whatevs',
            'location': 'New York',
            'dob': '2000-01-11',
            'country': 'USA',
            'pic': f,
        })
        o.close()