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docs/ccxt/wiki/examples/py/exchange-save-load-markets-cache.md

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+- [Exchange Save Load Markets Cache](./examples/py/)
+
+
+ ```python
+ # -*- coding: utf-8 -*-
+
+import asyncio
+import os
+from random import randint
+import sys
+from pprint import pprint
+
+
+import ccxt.pro as ccxt  # noqa: E402
+
+
+print('CCXT Version:', ccxt.__version__)
+
+exchange = ccxt.bybit({
+    # 'apiKey': 'YOUR_API_KEY',
+    # 'secret': 'YOUR_SECRET_KEY',
+})
+
+cache = {} # in this example we will save markets cache in this variable, but it can be saved in a file or database
+
+# We should use this strategy, when we need to recreate the exchange instance
+# multiple times, but we don't want to reload the cache every time
+# to avoid the extra time and resources needed to load the markets cache
+
+
+async def save_markets_cache():
+    global cache
+    before = exchange.milliseconds()
+
+    markets = await exchange.load_markets()
+
+    after = exchange.milliseconds()
+
+    print("Time to load markets:", after - before, "ms")
+
+    currencies = exchange.currencies
+
+    cache['markets'] = markets
+    cache['currencies'] = currencies
+
+
+async def instantiate_with_cache():
+    global cache
+
+    new_instance = ccxt.bybit({
+        'markets': cache['markets'],
+        'currencies': cache['currencies']
+    })
+
+    before = exchange.milliseconds()
+
+    await new_instance.load_markets()
+
+    after = exchange.milliseconds()
+
+    print ("Time to load markets with cache:", after - before, "ms") # as you can see, it is instanteous
+
+async def main():
+    try:
+        await save_markets_cache()
+
+        await instantiate_with_cache()
+
+    except Exception as e:
+        print(e)
+    await exchange.close()
+
+
+asyncio.run(main())
+
+
+# it should output something like this
+# CCXT Version: 4.4.38
+# Time to load markets: 1582 ms
+# Time to load markets with cache: 0 ms 
+```