Make S3Bucket easier to use

lib/nexrad/s3.py

@@ -1,6 +1,11 @@
 import re
 import datetime
 
+import boto3
+
+from botocore        import UNSIGNED
+from botocore.config import Config
+
 S3_BUCKET = 'noaa-nexrad-level2'
 S3_KEY_RE = re.compile(r'^(\d{4})/(\d{2})/(\d{2})/([A-Z]{4})/([A-Z]{4})(\d{4})(\d{2})(\d{2})_(\d{2})(\d{2})(\d{2})[_\.]')
 
@@ -28,8 +33,8 @@ class S3Bucket():
     name:  str
     cache: dict
 
-    def __init__(self, s3, name: str=S3_BUCKET):
-        self.s3    = s3
+    def __init__(self, name: str=S3_BUCKET):
+        self.s3    = boto3.client('s3', config=Config(signature_version=UNSIGNED))
         self.name  = name
         self.cache = dict()