<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def prune_cached(values):
 """Remove the items that have already been cached."""

    import os
    config_path = os.path.expanduser('~/.config/blockade')
    file_path = os.path.join(config_path, 'cache.txt')
    if not os.path.isfile(file_path):
        return values
    cached = [x.strip() for x in open(file_path, 'r').readlines()]
    output = list()
    for item in values:
        hashed = hash_values(item)
        if hashed in cached:
            continue
        output.append(item)
    return output