class_docstr: Sparse matrix where rows and columns are indexed using string.
  
  This matrix is used to store resutls of the competition evaluation.
class_docstr_tok: ["Sparse","matrix","where","rows","and","columns","are","indexed","using","string",".","This","matrix","is","used","to","store","resutls","of","the","competition","evaluation","."]
docstr: Sets element of the matrix at position indexed by key.
  
  Args:
    key: tuple of (row_idx, column_idx)
    value: new value of the element of the matrix
  
  Raises:
    IndexError: if key is invalid.
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code: def __setitem__(self, key, value):
      """Sets element of the matrix at position indexed by key.
  
      Args:
        key: tuple of (row_idx, column_idx)
        value: new value of the element of the matrix
  
      Raises:
        IndexError: if key is invalid.
      """
      if not isinstance(key, tuple) or len(key) != 2:
          raise IndexError("Invalid index: {0}".format(key))
      self._dim0.add(key[0])
      self._dim1.add(key[1])
      self._items[key] = value
  
imports: from __future__ import absolute_import
  from __future__ import division
  from __future__ import print_function
  import csv
  from io import BytesIO
  from io import StringIO
  import logging
  import os
  import pickle
  import time
  from six import iteritems
  from six import iterkeys
  from six import itervalues
  from six import PY3
label_desc: Use image node_id 5 for calling the ResultMatrix obj's underlying member method code with example usage: obj.__setitem__(key, value) without return types