Python: Optimisation de la fontion

def gmail_request(shop,req_type,ressource,endpoints="",post_data={}):
    global user_id,api_key,client_id,client_secret,refresh_token,access_tokens
    tries = 0
    #print(shop)
    while tries < 20:
        try:
            cont = "https://www.googleapis.com/gmail/v1/users/{}/{}?{}key={}".format(user_id[shop],ressource,endpoints,api_key[shop])
            if req_type == "get":
                r = requests.get(cont,headers={"Authorization":"OAuth {}".format(access_tokens[shop])}, timeout=15)
                print(r.json())
            elif req_type == "post":
                r = requests.post(cont,headers={"Authorization":"OAuth {}".format(access_tokens[shop])},json=post_data, timeout=15)
            if r.status_code > 300:
                data = {"client_id":client_id[shop],"client_secret":client_secret[shop],"refresh_token":refresh_token[shop],"grant_type":"refresh_token"}
                r2 = requests.post("https://www.googleapis.com/oauth2/v4/token",data=data, timeout=15)
                print(r2.json())
                access_tokens[shop] = r2.json()["access_token"]
                continue #retry a request with a new access_token
            break
        except:
            #print("connexion error on gmail, retrying...")
            time.sleep(10)
            tries += 1
    return r