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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 get_url(field):
 """Return file's url based on base url set in settings."""

    hydrated_path = _get_hydrated_path(field)
    base_url = getattr(settings, 'RESOLWE_HOST_URL', 'localhost')
    return "{}/data/{}/{}".format(base_url, hydrated_path.data_id, hydrated_path.file_name)