python foton binding failure on find_filter

In [3]: f = foton.find_filter("H1:CAL-CS")
---------------------------------------------------------------------------
FileNotFoundError                         Traceback (most recent call last)
Cell In[3], line 1
----> 1 f = foton.find_filter("H1:CAL-CS")

File /var/opt/conda/base/envs/cds/lib/python3.9/site-packages/foton.py:160, in find_filter(chan, chans_path)
    158 excpat = r'\[{}_EXCMON\]'.format(chan)
    159 iniglob = chans_path + '/daq/' + '*.ini'
--> 160 inifiles = pygrep(iniglob, excpat)
    161 filterfile_candidates = [ini_to_filterfile(filename) for filename in inifiles]
    163 matches = []

File /var/opt/conda/base/envs/cds/lib/python3.9/site-packages/foton.py:121, in find_filter.<locals>.pygrep(fileglob, pattern)
    119 pattern = re.compile(pattern)
    120 for filename in glob.iglob(fileglob):
--> 121     with open(filename, 'r') as f:
    122         try:
    123             if pattern.search(f.read()):

FileNotFoundError: [Errno 2] No such file or directory: '/opt/rtcds/lho/h1/chans/daq/H0EDCU_VAC.ini'

In [4]: 

I'm not sure why it's looking for H0EDCU_VAN.ini when it's supposed to be looking for foton files, but I note that '/opt/rtcds/lho/h1/chans/daq/H0EDCU_VAC.ini' is actually a broken soft link.