Network annotation file incorrect error

[JGASmits]

When running ananse binding, with a costum bedfile with the wrong chromosome identifiers, the error is:

2021-03-05 14:03:23 | INFO | Loading expression
2021-03-05 14:04:39 | INFO | creating expression dataframe
2021-03-05 14:05:51 | INFO | Aggregate binding
2021-03-05 14:05:51 | INFO | reading enhancers
Traceback (most recent call last):
File "/vol/mbconda/jsmits/envs/ananse_dev/lib/python3.8/site-packages/pandas/core/indexes/base.py", line 2898, in get_loc
return self._engine.get_loc(casted_key)
File "pandas/_libs/index.pyx", line 70, in pandas._libs.index.IndexEngine.get_loc
File "pandas/_libs/index.pyx", line 101, in pandas._libs.index.IndexEngine.get_loc
File "pandas/_libs/hashtable_class_helper.pxi", line 1675, in pandas._libs.hashtable.PyObjectHashTable.get_item
File "pandas/_libs/hashtable_class_helper.pxi", line 1683, in pandas._libs.hashtable.PyObjectHashTable.get_item
KeyError: 'Start_b'
The above exception was the direct cause of the following exception:
Traceback (most recent call last):
File "/vol/mbconda/jsmits/envs/ananse_dev/bin/ananse", line 371, in
args.func(args)
File "/vol/mbconda/jsmits/envs/ananse_dev/lib/python3.8/site-packages/ananse/commands/network.py", line 28, in network
b.run_network(
File "/vol/mbconda/jsmits/envs/ananse_dev/lib/python3.8/site-packages/ananse/network.py", line 552, in run_network
df_binding = self.aggregate_binding(
File "/vol/mbconda/jsmits/envs/ananse_dev/lib/python3.8/site-packages/ananse/network.py", line 372, in aggregate_binding
gene_df = self.enhancer2gene(
File "/vol/mbconda/jsmits/envs/ananse_dev/lib/python3.8/site-packages/ananse/network.py", line 274, in enhancer2gene
(genes["Start_b"] + genes["End_b"]) / 2 - genes["Start"]
File "/vol/mbconda/jsmits/envs/ananse_dev/lib/python3.8/site-packages/pandas/core/frame.py", line 2906, in getitem
indexer = self.columns.get_loc(key)
File "/vol/mbconda/jsmits/envs/ananse_dev/lib/python3.8/site-packages/pandas/core/indexes/base.py", line 2900, in get_loc
raise KeyError(key) from err
KeyError: 'Start_b'

Changing this to a more insightfull error message would be nice. :)

Gr