<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def load_precision(filename):
 """ Load a CLASS precision file into a dictionary. Parameters filename : str the name of an existing file to load, or one in the files included as part of the CLASS source Returns ------- dict : the precision parameters loaded from file """

    # also look in data dir
    path = _find_file(filename)

    r = dict()
    with open(path, 'r') as f:
        exec(f.read(), {}, r)

    return r