Pretty prints a mongoengine.Document.

pprint_doc

def pprint_doc(doc, level=1):
  '''Pretty prints a `mongoengine.Document`.'''
  body = ['<', type(doc).__name__, ':']
  # for field in sorted(doc._fields, key=lambda f: f.number):
  for key, field in doc._fields.iteritems():
    value = doc[key]
    if value is not None:
      body.append('\n%s%s: %s' % (' '.join([' ' for idx in range(level)]),  key, repr(value)))
  body.append('>')
  return ''.join(body)

class PPrintMixin should inherit from object, mongoengine will inspect and will raise an AttributeError because of no __class__ attribute