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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_for_object(self, parent_object, slot, role='m', title=None):
 """ Create a placeholder with the given parameters """

        from .db import Placeholder
        parent_attrs = get_parent_lookup_kwargs(parent_object)
        obj = self.create(
            slot=slot,
            role=role or Placeholder.MAIN,
            title=title or slot.title().replace('_', ' '),
            **parent_attrs
        )
        obj.parent = parent_object  # fill the reverse cache
        return obj