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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 forcemerge(self, index=None, params=None):
 """ The force merge API allows to force merging of one or more indices through an API. The merge relates to the number of segments a Lucene index holds within each shard. The force merge operation allows to reduce the number of segments by merging them. This call will block until the merge is complete. If the http connection is lost, the request will continue in the background, and any new requests will block until the previous force merge is complete. `<http://www.elastic.co/guide/en/elasticsearch/reference/current/indices-forcemerge.html>`_ :arg index: A comma-separated list of index names; use `_all` or empty string to perform the operation on all indices :arg allow_no_indices: Whether to ignore if a wildcard indices expression resolves into no concrete indices. (This includes `_all` string or when no indices have been specified) :arg expand_wildcards: Whether to expand wildcard expression to concrete indices that are open, closed or both., default 'open', valid choices are: 'open', 'closed', 'none', 'all' :arg flush: Specify whether the index should be flushed after performing the operation (default: true) :arg ignore_unavailable: Whether specified concrete indices should be ignored when unavailable (missing or closed) :arg max_num_segments: The number of segments the index should be merged into (default: dynamic) :arg only_expunge_deletes: Specify whether the operation should only expunge deleted documents :arg operation_threading: TODO: ? """

        return self.transport.perform_request(
            "POST", _make_path(index, "_forcemerge"), params=params
        )