保留小数、并且加百分号

python
from decimal import *
def formatting_str(number_, keep_digits, is_percent=False):
    """
    number 为数字、字符串
    keep_digits 必为整数 0 代表不做保留整数
    is_percent Boolean
    :return ''或结果
    """

    # rate保留2位小数，
    str_ = str(number_).replace('%', '')
    result = ''
    try:
        if keep_digits != '0':
            Decimal(str_)
            query = '{:.' + str(keep_digits) + 'f}'
            result = query.format(Decimal(str_))
        else:
            if str_:
                result = str_
        if is_percent and (str_ or keep_digits != '0'):
            result += '%'
    except:
        pass
    return result