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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 post_field_cache(self, field_cache):
 """Where field_cache is a list of fields' mappings"""

        index_pattern = self.field_cache_to_index_pattern(field_cache)
        # self.pr_dbg("request/post: %s" % index_pattern)
        resp = requests.post(self.post_url, data=index_pattern).text
        # resp = {"_index":".kibana","_type":"index-pattern","_id":"aaa*","_version":1,"created":true}  # noqa
        resp = json.loads(resp)
        return 0