check_file() assert unique

utils/general.py

@@ -133,7 +133,8 @@ def check_file(file):
     else:
         files = glob.glob('./**/' + file, recursive=True)  # find file
         assert len(files), 'File Not Found: %s' % file  # assert file was found
-        return files[0]  # return first file if multiple found
+        assert len(files) == 1, "Multiple files match '%s', specify exact path: %s" % (file, files)  # assert unique
+        return files[0]  # return file
 
 
 def check_dataset(dict):