[fix] small fix for graceful error handling of invalid DOI/ID

README.md

@@ -1,10 +1,10 @@
 zenodo_get: a downloader for Zenodo records
 ===========================================
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src/zenodo_get.py

@@ -156,7 +156,11 @@ def check_hash(filename, checksum):
         url = options.doi
         if not url.startswith('http'):
             url = 'https://doi.org/'+url
-        r = requests.get(url)
+        try:
+            r = requests.get(url)
+        except:
+            eprint('Connection error. Please, check the DOI/ID, and try again later.')
+            sys.exit(1)
         if not r.ok:
             eprint('DOI could not be resolved. Try again, or use record ID.')
             sys.exit(1)