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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 _HandleApi(self, request):
 """Handles API requests."""

    # Checks CSRF token. CSRF token cookie is updated when homepage is visited
    # or via GetPendingUserNotificationsCount API call.
    ValidateCSRFTokenOrRaise(request)

    response = http_api.RenderHttpResponse(request)

    # GetPendingUserNotificationsCount is an API method that is meant
    # to be invoked very often (every 10 seconds). So it's ideal
    # for updating the CSRF token.
    # We should also store the CSRF token if it wasn't yet stored at all.
    if (("csrftoken" not in request.cookies) or response.headers.get(
        "X-API-Method", "") == "GetPendingUserNotificationsCount"):
      StoreCSRFCookie(request.user, response)

    return response