code: def collect_blobs(blob_service, container, pattern=None):
      
      if not blob_service:
          raise ValueError('missing parameter blob_service')
  
      if not container:
          raise ValueError('missing parameter container')
  
      if not _pattern_has_wildcards(pattern):
          return [pattern] if blob_service.exists(container, pattern) else []
  
      results = []
      for blob in blob_service.list_blobs(container):
          try:
              blob_name = blob.name.encode(
                  'utf-8') if isinstance(blob.name, unicode) else blob.name
          except NameError:
              blob_name = blob.name
  
          if not pattern or _match_path(blob_name, pattern):
              results.append(blob_name)
  
      return results
docs: List the blobs in the given blob container, filter the blob by comparing their path to the given pattern.