diff --git a/api/core.py b/api/core.py
index 4312db9..059b122 100644
--- a/api/core.py
+++ b/api/core.py
@@ -149,8 +149,9 @@ async def run_checks(incoming_request: fastapi.Request):
 async def get_crypto_price(cryptocurrency: str) -> float:
     """Gets the price of a cryptocurrency using coinbase's API."""
 
+    cache_path = os.path.join('cache', 'crypto_prices.json')
     try:
-        async with aiofiles.open(os.path.join('cache', 'crypto_prices.json')) as f:
+        async with aiofiles.open(cache_path) as f:
             content = await f.read()
     except FileNotFoundError:
         cache = {}
@@ -167,7 +168,7 @@ async def get_crypto_price(cryptocurrency: str) -> float:
             cache[cryptocurrency] = usd_price
             cache['_last_updated'] = time.time()
 
-            async with aiofiles.open(os.path.join('cache', 'crypto_prices.json'), 'w') as f:
+            async with aiofiles.open(cache_path, 'w') as f:
                 for chunk in json.JSONEncoder().iterencode(cache):
                     await f.write(chunk)