drop lmdb database using python
<p>I would like to drop an lmdb database.  The following hits 'typerror:invalid type' on the txn.drop(db_name) line.</p>

<pre><code>import lmdb 
def kill_db(db_name):
    print('ABOUT TO DELETE DB '+str(db_name)+'!!!!')
    raw_input('press enter to continue or ctrl-C to not')
    env = lmdb.open(db_name, readonly=False)
    txn = lmdb.Transaction(env)
    txn.drop(db_name)
</code></pre>

<p>any clues as to why this is happening? 
I am new to lmdb (as you may have guessed) so be gentle.</p>