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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 _initialize_repo_cache():
 """Initialize the repository cache used for scraping. Retrieves a list of repositories with their provider and last scraping time from Elasticsearch. This list can be used to check which repos need to be scraped (e.g. after a specific amount of time). """

    LOGGER.info("Initializing repository cache")
    # Initialize Repo Cache
    repo_cache = {}

    # Get all repos from Elasticsearch
    for hit in GitRepo.search().query("match_all").scan():
        # TODO (fschmidt): Maybe we can use this list as cache for the whole
        # scraper-webhook part.
        # This way, we could reduce the amount of operations needed for GitHub
        # and ElasticSearch
        repo_cache[hit.repo_name] = hit.to_dict(skip_empty=False)

    return repo_cache