🐛 Change LightningLoggerBase to Logger

[julien-blanchon]

What does this PR do?

Fix cannot import name 'LightningLoggerBase' from 'pytorch_lightning.loggers'. Since pytorch_lightning.loggers.base.LightningLoggerBase is deprecated over pytorch_lightning.loggers.base.Logger.
Fixes #972

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[ludwigwinkler]

Is there a workaround at the moment by installing an older version?

[senarvi]

If we want to maintain compatibility to older versions, then we could do something like this:

try:
    from pytorch_lightning.loggers import Logger
except ImportError:
    from pytorch_lightning.loggers import LightningLoggerBase
    Logger = LightningLoggerBase

[julien-blanchon]

@senarvi I did commit your idea to maintain older version compatibility

[D0miH]

Any updates on this? Having to change LightningLoggerBase to Logger every time I re-install the package is kinda tedious.

[tedtroxell]

Are we able to get this merged? I'm willing to help out any way possible. It seems like not being able to use lightning bolts with the latest pytorch lightning seems like a big deal