Change help_text in bitcoin-util-test.py to a docstring.

test/util/bitcoin-util-test.py

@@ -3,23 +3,23 @@
 # Copyright 2016 The Bitcoin Core developers
 # Distributed under the MIT software license, see the accompanying
 # file COPYING or http://www.opensource.org/licenses/mit-license.php.
-import os
+"""Test framework for bitcoin utils.
-import sys
-import argparse
-import logging
-
-help_text="""Test framework for bitcoin utils.
 
 Runs automatically during `make check`.
 
 Can also be run manually."""
 
+import os
+import sys
+import argparse
+import logging
+
 if __name__ == '__main__':
     sys.path.append(os.path.dirname(os.path.abspath(__file__)))
     import buildenv
     import bctest
 
-    parser = argparse.ArgumentParser(description=help_text)
+    parser = argparse.ArgumentParser(description=__doc__)
     parser.add_argument('-v', '--verbose', action='store_true')
     args = parser.parse_args()
     verbose = args.verbose