def get_file_mapping(syn, release_folder_synid):
    """
    Get file mapping between important files needed for dashboard and
    their synapse ids

    Args:
        syn:  synapse object
        release_folder_synid: synapse id of release

    """
    files = syn.getChildren(release_folder_synid)
    file_mapping = dict()
    for metadata in files:
        filename = metadata['name']
        synid = metadata['id']
        if not filename.startswith('meta'):
            if filename.startswith('data_clinical_sample'):
                file_mapping['clinical'] = synid
            elif filename.endswith('fusions.txt'):
                file_mapping['fusion'] = synid
            elif filename.endswith('CNA.txt'):
                file_mapping['cna'] = synid
            elif filename.endswith('.seg'):
                file_mapping['seg'] = synid
    return file_mapping
