from app import app
import hashlib


@app.template_filter('none_filter')
def none_filter(value):
    if value is None:
        return ''
    else:
        return value


@app.template_filter('md5')
def md5_filter(value):
    m = hashlib.md5()
    m.update(str(value).encode('UTF-8'))
    return m.hexdigest()


@app.template_filter('str')
def str_filter(value):
    return str(value)