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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def assert_matching_time_coord(arr1, arr2):
 """Check to see if two DataArrays have the same time coordinate. Parameters arr1 : DataArray or Dataset First DataArray or Dataset arr2 : DataArray or Dataset Second DataArray or Dataset Raises ------ ValueError If the time coordinates are not identical between the two Datasets """

    message = ('Time weights not indexed by the same time coordinate as'
               ' computed data.  This will lead to an improperly computed'
               ' time weighted average.  Exiting.\n'
               'arr1: {}\narr2: {}')
    if not (arr1[TIME_STR].identical(arr2[TIME_STR])):
        raise ValueError(message.format(arr1[TIME_STR], arr2[TIME_STR]))