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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 _replication_request(command, host=None, core_name=None, params=None):
    '''
    PRIVATE METHOD
    Performs the requested replication command and returns a dictionary with
    success, errors and data as keys. The data object will contain the JSON
    response.

    command : str
        The replication command to execute.
    host : str (None)
        The solr host to query. __opts__['host'] is default
    core_name: str (None)
        The name of the solr core if using cores. Leave this blank if you are
        not using cores or if you want to check all cores.
    params : list<str> ([])
        Any additional parameters you want to send. Should be a lsit of
        strings in name=value format. e.g. ['name=value']

    Return: dict<str, obj>::

        {'success':boolean, 'data':dict, 'errors':list, 'warnings':list}
    '''
    params = [] if params is None else params
    extra = ["command={0}".format(command)] + params
    url = _format_url('replication', host=host, core_name=core_name,
                      extra=extra)
    return _http_request(url)