Use the num_filters property to return the total number of filters available in the FilterManager.
Example
>>> from teradataml import DataFrame, load_example_data, FilterManager
>>> load_example_data('dataframe', 'admissions_train')
>>> df = DataFrame("admissions_train")
>>> fm = FilterManager(repo='vfs_v1', name='stats_filter_manager')
>>> fm.load_filter(df=df.groupby('stats').count()[['stats']])
True
>>> fm.num_filters
3