Need an identity operator because lambda is too slow

[Paul Rubin]

"Deron Meranda" <deron.meranda at gmail.com> writes:
>     do_transform = some_rare_condition
>     for item in some_sequence:
>         if do_transform:
>             item2 = transform_function(item)
>         else:
>             item2 = item
>         ..... # more stuff

This might be a little more direct:

    from itertools import imap
    if some_rare_condition:
       mapped_sequence = imap(transform_function, some_sequence)
    else:
       mapped_sequence = some_sequence

    for item in mapped_sequence:
        # more stuff

I agree that an identity function would be useful.  I think I
suggested it a long time ago and didn't get much interest.