def batch_get_traces(TraceIds=None, NextToken=None):
    """
    Retrieves a list of traces specified by ID. Each trace is a collection of segment documents that originates from a single request. Use GetTraceSummaries to get a list of trace IDs.
    See also: AWS API Documentation
    
    
    :example: response = client.batch_get_traces(
        TraceIds=[
            'string',
        ],
        NextToken='string'
    )
    
    
    :type TraceIds: list
    :param TraceIds: [REQUIRED]
            Specify the trace IDs of requests for which to retrieve segments.
            (string) --
            

    :type NextToken: string
    :param NextToken: Pagination token. Not used.

    :rtype: dict
    :return: {
        'Traces': [
            {
                'Id': 'string',
                'Duration': 123.0,
                'Segments': [
                    {
                        'Id': 'string',
                        'Document': 'string'
                    },
                ]
            },
        ],
        'UnprocessedTraceIds': [
            'string',
        ],
        'NextToken': 'string'
    }
    
    
    :returns: 
    (string) --
    
    """
    pass
