def get_substring_or_empty(data, start, end=''):
    if (start in data):
        if ('' == start):
            f = 0
        else:
            f = len(start)
            f = (data.find(start) + f)
        data = data[f:]
    else:
        return ''
    if (end in data):
        if ('' == end):
            f = len(data)
        else:
            f = data.find(end)
        data = data[:f]
    else:
        return ''
    data = data.strip()
    return data
def get_substring_or_empty(data, start, end=):
    if (start in data):
        if ( == start):
            f = 0
        else:
            f = len(start)
            f = (data.find(start) + f)
        data = data[f:]
    else:
        return 
    if (end in data):
        if ( == end):
            f = len(data)
        else:
            f = data.find(end)
        data = data[:f]
    else:
        return 
    data = data.strip()
    return data