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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 connect_entry_signals():
 """ Connect all the signals on Entry model. """

    post_save.connect(
        ping_directories_handler, sender=Entry,
        dispatch_uid=ENTRY_PS_PING_DIRECTORIES)
    post_save.connect(
        ping_external_urls_handler, sender=Entry,
        dispatch_uid=ENTRY_PS_PING_EXTERNAL_URLS)
    post_save.connect(
        flush_similar_cache_handler, sender=Entry,
        dispatch_uid=ENTRY_PS_FLUSH_SIMILAR_CACHE)
    post_delete.connect(
        flush_similar_cache_handler, sender=Entry,
        dispatch_uid=ENTRY_PD_FLUSH_SIMILAR_CACHE)