from typing import Dict


def _filter_frequency(ngrams: Dict[str, int], min_freq: int) -> Dict[str, int]:
    """
    Filter a ngram list for ngrams with a minimum frequency.

    :param ngrams:
    :param min_freq:
    :return:
    """
    output = {}
    for (ngram, freq) in ngrams.items():
        if freq >= min_freq:
            output[ngram] = freq
    return output