AsyncSession: change acurl to a lazy property, so that the instance c…

…an be created out of async world

curl_cffi/requests/session.py

@@ -606,8 +606,8 @@ def __init__(
             ```
         """
         super().__init__(**kwargs)
-        self.loop = loop if loop is not None else asyncio.get_running_loop()
-        self.acurl = async_curl if async_curl is not None else AsyncCurl(loop=self.loop)
+        self.loop = loop
+        self._acurl = async_curl
         self.max_clients = max_clients
         self.reset()
         if sys.version_info >= (3, 8) and sys.platform.lower().startswith("win"):
@@ -616,6 +616,14 @@ def __init__(
             ):
                 warnings.warn(WINDOWS_WARN)
 
+    @property
+    def acurl(self):
+        if self.loop is None:
+            self.loop = asyncio.get_running_loop()
+        if self._acurl is None:
+            self._acurl = AsyncCurl(loop=self.loop)
+        return self._acurl
+
     def reset(self):
         self.pool = asyncio.LifoQueue(self.max_clients)
         while True: