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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def check_key(request):
 """ Check to see if we already have an access_key stored, if we do then we have already gone through OAuth. If not then we haven't and we probably need to. """

    try:
        access_key = request.session.get('oauth_token', None)
        if not access_key:
            return False
    except KeyError:
        return False
    return True