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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 capture(self, function=None, prefix=None):
 """ Decorator to turn a function into a captured function. The missing arguments of captured functions are automatically filled from the configuration if possible. See :ref:`captured_functions` for more information. If a ``prefix`` is specified, the search for suitable entries is performed in the corresponding subtree of the configuration. """

        if function in self.captured_functions:
            return function
        captured_function = create_captured_function(function, prefix=prefix)
        self.captured_functions.append(captured_function)
        return captured_function