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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 add_dependency(self, source, target, action):
 ''' Create a dependency between fields source and target via callable action. 
)['Address']
        >>> permuter.add_dependency('one', 'two', lambda val: max(0,val-1))
        >>> for obj in permuter.linear():
        ...   print("obj = {}".format(obj))
        ...
        obj = one: 0
        two: 1

        obj = one: 256
        two: 257

        obj = one: 4096
        two: 4097

        obj = one: 1073741823
        two: 1073741824


        '''
        self._dependencies.append((source, target, action))