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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def get_resource(request):
 """Retrieve a file's data."""

    hash = request.matchdict['hash']

    # Do the file lookup
    with db_connect() as db_connection:
        with db_connection.cursor() as cursor:
            args = dict(hash=hash)
            cursor.execute(SQL['get-resource'], args)
            try:
                mimetype, file = cursor.fetchone()
            except TypeError:  # None returned
                raise httpexceptions.HTTPNotFound()

    resp = request.response
    resp.status = "200 OK"
    resp.content_type = mimetype
    resp.body = file[:]
    return resp