authenticity_token problem

[allVentures]

21:56:33 - Retrieved login page.
Traceback (most recent call last):
File "500px.py", line 255, in
loginParams['authenticity_token'] = loginPage_soup.find('meta', {'name': 'csrf-token'}).get('content')
AttributeError: 'NoneType' object has no attribute 'get'

how can this be fixxed?