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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 _requests(self, url, method='GET', headers=None, params=None, data=None, errors=None):

        ''' a helper method for relaying requests from client to api '''

        title = '%s._requests' % self.__class__.__name__
    
    # import dependencies
        from time import time
        import requests

    # validate access token
        if not self._access_token:
            self.access_token()
            if self.retrieve_details:
                self._get_products()
    
    # refresh token
        current_time = time()
        if current_time > self.expires_at:
            self.access_token()
            if self.retrieve_details:
                self._get_products()

    # construct request kwargs
        request_kwargs = {
            'url': url,
            'headers': { 
                'Authorization': 'Bearer %s' % self._access_token,
                'Accept': 'application/json;v=2'
            },
            'params': {},
            'data': {}
        }
        if headers:
            request_kwargs['headers'].update(headers)
        if params:
            request_kwargs['params'].update(params)
        if data:
            request_kwargs['data'].update(data)

    # send request
        if method == 'POST':
            try:
                response = requests.post(**request_kwargs)
            except Exception:
                if self.requests_handler:
                    request_kwargs['method'] = 'POST'
                    request_object = requests.Request(**request_kwargs)
                    return self.requests_handler(request_object)
                else:
                    raise
        elif method == 'GET':
            try:
                response = requests.get(**request_kwargs)
            except Exception:
                if self.requests_handler:
                    request_kwargs['method'] = 'GET'
                    request_object = requests.Request(**request_kwargs)
                    return self.requests_handler(request_object)
                else:
                    raise
        else:
            raise ValueError('%s(method='') must be either GET or POST' % title)

    # handle response
        response_details = self.response_handler.handle(response, errors)
        
        return response_details