def _get_color_definitions(data):
    """Returns the list of custom color definitions for the TikZ file.
    """
    definitions = []
    ff = data['float format']
    for name, rgb in data['custom colors'].items():
        definitions.append(
            f'\\definecolor{{{name}}}{{rgb}}{{{rgb[0]:{ff}},{rgb[1]:{ff}},{rgb[2]:{ff}}}}'
            )
    return definitions
