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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 populate_source(cls, source):
 """Derive missing values of source from the existing fields."""

        # Only URL pararemter is mandatory, let the KeyError be thrown.
        if "name" not in source:
            source["name"] = get_url_name(source["url"])
        if "verify_ssl" not in source:
            source["verify_ssl"] = "https://" in source["url"]
        if not isinstance(source["verify_ssl"], bool):
            source["verify_ssl"] = source["verify_ssl"].lower() == "true"
        return source