def ensure_pad(name, pad="<STR_LIT:_>"):
if not name or name[<NUM_LIT:0>] == name[-<NUM_LIT:1>] == pad:<EOL><INDENT>return name<EOL><DEDENT>else:<EOL><INDENT>return "<STR_LIT>" % (pad, name, pad)<EOL><DEDENT>
Examples:
    >>> ensure_pad('conda')
    '_conda_'