new_contents: from util import pklload
  from collections import defaultdict
  import indra.tools.assemble_corpus as ac
  
  
  if __name__ == '__main__':
      # Load cached Statements just before going into the model
      stmts = pklload('pysb_stmts')
  
      # Start a dictionary for source counts
      sources_count = defaultdict(int)
      # Count statements according to sources of evidence
      for stmt in stmts:
          sources = tuple(sorted(list(set([ev.source_api for ev in stmt.evidence]))))
          sources_count[sources] += 1
  
      # Statements from databases only
      db_only = 0
      # Statements from reading only
      reading_only = 0
      # Statements from databases and reading
      mixture = 0
      # Database sources
      dbs = set(['bel', 'biopax', 'phosphosite', 'signor'])
      # Reader sources
      readers = set(['reach', 'trips', 'sparser', 'r3'])
      for k, v in sources_count.items():
          d = set(k).intersection(dbs)
          r = set(k).intersection(readers)
          if d and r:
              mixture += v
          if d and not r:
              db_only += v
          if r and not d:
              reading_only += v
  
      for k, v in sorted(sources_count.items(), key=lambda x: x[1]):
          print(k, v)
  
subject: Add script to get evidence sources