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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 setup():
 """ Create the index template in elasticsearch specifying the mappings and any settings to be used. This can be run at any time, ideally at every new code deploy. """

    # create an index template
    index_template = BlogPost._index.as_template(ALIAS, PATTERN)
    # upload the template into elasticsearch
    # potentially overriding the one already there
    index_template.save()

    # create the first index if it doesn't exist
    if not BlogPost._index.exists():
        migrate(move_data=False)