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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 get_builds(galaxy_base):
 """Retrieve configured genome builds and reference files, using Galaxy configuration files. Allows multiple dbkey specifications in the same file, using the most recently added. """

    name = "samtools"
    galaxy_config = _get_galaxy_tool_info(galaxy_base)
    galaxy_dt = _get_galaxy_data_table(name, galaxy_config["tool_data_table_config_path"])
    loc_file, need_remap = _get_galaxy_loc_file(name, galaxy_dt, galaxy_config["tool_data_path"],
                                                galaxy_base)
    assert not need_remap, "Should not need to remap reference files"
    fnames = {}
    for dbkey, fname in _galaxy_loc_iter(loc_file, galaxy_dt):
        fnames[dbkey] = fname
    out = []
    for dbkey in sorted(fnames.keys()):
        out.append((dbkey, fnames[dbkey]))
    return out