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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 _webTranslator(store, fallback):
 """ Discover a web translator based on an Axiom store and a specified default. Prefer the specified default. This is an implementation detail of various initializers in this module which require an L{IWebTranslator} provider. Some of those initializers did not previously require a webTranslator, so this function will issue a L{UserWarning} if no L{IWebTranslator} powerup exists for the given store and no fallback is provided. @param store: an L{axiom.store.Store} @param fallback: a provider of L{IWebTranslator}, or None @return: 'fallback', if it is provided, or the L{IWebTranslator} powerup on 'store'. """

    if fallback is None:
        fallback = IWebTranslator(store, None)
        if fallback is None:
            warnings.warn(
                "No IWebTranslator plugin when creating Scrolltable - broken "
                "configuration, now deprecated!  Try passing webTranslator "
                "keyword argument.", category=DeprecationWarning,
                stacklevel=4)
    return fallback