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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 _get_updated_values(before_values, after_values):
 """ Get updated values from 2 dicts of values Args: before_values (dict):
 values before update after_values (dict):
 values after update Returns: dict: a diff dict with key is field key, value is tuple of (before_value, after_value) """

    assert before_values.keys() == after_values.keys()
    return dict([(k, [before_values[k], after_values[k]])
                 for k in before_values.keys()
                 if before_values[k] != after_values[k]])