Do not perform summary if blast is empty

[svarona]

Sometimes, mapping founds a plasmid, but then BLAST doesn't find any contig matching the plasmid to generate the summary, and plasmidID crushes with:

CREATING SUMMARY REPORT (Fri Jul 12 09:15:06 CEST 2024)
 An html report with miniatures of the images will be generate with useful statistics to determine the correct plasmids in the sample.
Namespace(group=False, input_folder='/scratch/bi/SRVCNM1171_20240711_SPYOGENES07_svaldezate_S/ANALYSIS/20240711_ANALYSIS03_PLASMIDID/NO_GROUP/20231359')
Creating summary
Wrong number of items passed 7, placement implies 1
Traceback (most recent call last):
  File "/usr/local/lib/python3.7/site-packages/pandas/core/indexes/base.py", line 3080, 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 4554, in pandas._libs.hashtable.PyObjectHashTable.get_item
  File "pandas/_libs/hashtable_class_helper.pxi", line 4562, in pandas._libs.hashtable.PyObjectHashTable.get_item
KeyError: 'images'

The above exception was the direct cause of the following exception:

Traceback (most recent call last):
  File "/usr/local/lib/python3.7/site-packages/pandas/core/generic.py", line 3826, in _set_item
    loc = self._info_axis.get_loc(key)
  File "/usr/local/lib/python3.7/site-packages/pandas/core/indexes/base.py", line 3082, in get_loc
    raise KeyError(key) from err
KeyError: 'images'

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/usr/local/bin/summary_report_pid.py", line 465, in <module>
    main()
  File "/usr/local/bin/summary_report_pid.py", line 458, in main
    final_individual_dataframe = include_images(input_folder, summary_df)
  File "/usr/local/bin/summary_report_pid.py", line 135, in include_images
    summary_df['images'] = summary_df.apply(lambda x: image_finder(x, sample_folder), axis=1)
  File "/usr/local/lib/python3.7/site-packages/pandas/core/frame.py", line 3163, in __setitem__
    self._set_item(key, value)
  File "/usr/local/lib/python3.7/site-packages/pandas/core/frame.py", line 3243, in _set_item
    NDFrame._set_item(self, key, value)
  File "/usr/local/lib/python3.7/site-packages/pandas/core/generic.py", line 3829, in _set_item
    self._mgr.insert(len(self._info_axis), key, value)
  File "/usr/local/lib/python3.7/site-packages/pandas/core/internals/managers.py", line 1203, in insert
    block = make_block(values=value, ndim=self.ndim, placement=slice(loc, loc + 1))
  File "/usr/local/lib/python3.7/site-packages/pandas/core/internals/blocks.py", line 2742, in make_block
    return klass(values, ndim=ndim, placement=placement)
  File "/usr/local/lib/python3.7/site-packages/pandas/core/internals/blocks.py", line 143, in __init__
    f"Wrong number of items passed {len(self.values)}, "
ValueError: Wrong number of items passed 7, placement implies 1
Traceback (most recent call last):
  File "/usr/local/lib/python3.7/site-packages/pandas/core/indexes/base.py", line 3080, 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 4554, in pandas._libs.hashtable.PyObjectHashTable.get_item
  File "pandas/_libs/hashtable_class_helper.pxi", line 4562, in pandas._libs.hashtable.PyObjectHashTable.get_item
KeyError: 'images'

The above exception was the direct cause of the following exception:

Traceback (most recent call last):
  File "/usr/local/lib/python3.7/site-packages/pandas/core/generic.py", line 3826, in _set_item
    loc = self._info_axis.get_loc(key)
  File "/usr/local/lib/python3.7/site-packages/pandas/core/indexes/base.py", line 3082, in get_loc
    raise KeyError(key) from err
KeyError: 'images'

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/usr/local/bin/summary_report_pid.py", line 465, in <module>
    main()
  File "/usr/local/bin/summary_report_pid.py", line 458, in main
    final_individual_dataframe = include_images(input_folder, summary_df)
  File "/usr/local/bin/summary_report_pid.py", line 135, in include_images
    summary_df['images'] = summary_df.apply(lambda x: image_finder(x, sample_folder), axis=1)
  File "/usr/local/lib/python3.7/site-packages/pandas/core/frame.py", line 3163, in __setitem__
    self._set_item(key, value)
  File "/usr/local/lib/python3.7/site-packages/pandas/core/frame.py", line 3243, in _set_item
    NDFrame._set_item(self, key, value)
  File "/usr/local/lib/python3.7/site-packages/pandas/core/generic.py", line 3829, in _set_item
    self._mgr.insert(len(self._info_axis), key, value)
  File "/usr/local/lib/python3.7/site-packages/pandas/core/internals/managers.py", line 1203, in insert
    block = make_block(values=value, ndim=self.ndim, placement=slice(loc, loc + 1))
  File "/usr/local/lib/python3.7/site-packages/pandas/core/internals/blocks.py", line 2742, in make_block
    return klass(values, ndim=ndim, placement=placement)
  File "/usr/local/lib/python3.7/site-packages/pandas/core/internals/blocks.py", line 143, in __init__
    f"Wrong number of items passed {len(self.values)}, "
ValueError: Wrong number of items passed 7, placement implies 1

Possible solution: Do not perform summary when there are no BLAST hits.