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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 create_entry_tag(sender, instance, created, **kwargs):
 """ Creates EntryTag for Entry corresponding to specified ItemBase instance. :param sender: the sending ItemBase class. :param instance: the ItemBase instance. """

    from ..models import (
        Entry,
        EntryTag
    )

    entry   = Entry.objects.get_for_model(instance.content_object)[0]
    tag     = instance.tag

    if not EntryTag.objects.filter(tag=tag, entry=entry).exists():
        EntryTag.objects.create(tag=tag, entry=entry)