Update element_array_ephys/export/nwb/nwb.py

Co-authored-by: Kabilar Gunalan <kabilar@datajoint.com>

Author: bendichter

element_array_ephys/export/nwb/nwb.py

@@ -51,7 +51,7 @@ def __init__(self, lfp_electrodes_query, chunk_length: int = 10000):
 
         first_record = (
             self.lfp_electrodes_query & dict(electrode=self.electrodes[0])
-        ).fetch(as_dict=True)[0]
+        ).fetch1(as_dict=True)
 
         self.n_channels = len(lfp_electrodes_query)
         self.n_tt = len(first_record["lfp"])