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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 access_cookie(self, account):
 """Make and store access cookie for a given account. If account is allowed then make a cookie and add it to the dict of accepted access cookies with current timestamp as the value. Return the access cookie. Otherwise return None. """

        if (self.account_allowed(account)):
            cookie = self._generate_random_string(self.access_cookies)
            self.access_cookies[cookie] = int(time.time())
            return cookie
        else:
            return None