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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 walk(self, function, raise_errors=True, call_on_sections=False, **keywargs):
 """ Walk every member and call a function on the keyword and value. Return a dictionary of the return values If the function raises an exception, raise the errror unless ``raise_errors=False``, in which case set the return value to ``False``. Any unrecognised keyword arguments you pass to walk, will be pased on to the function you pass in. Note: if ``call_on_sections`` is ``True`` then - on encountering a subsection, *first* the function is called for the *whole* subsection, and then recurses into it's members. This means your function must be able to handle strings, dictionaries and lists. This allows you to change the key of subsections as well as for ordinary members. The return value when called on the whole subsection has to be discarded. See the encode and decode methods for examples, including functions. admonition:: caution You can use ``walk`` to transform the names of members of a section but you mustn't add or delete members. ConfigObj({'XXXXsection': {'XXXXkey': 'XXXXvalue'}}) {'CLIENT1section': {'CLIENT1key': None}} ConfigObj({'CLIENT1section': {'CLIENT1key': 'CLIENT1value'}}) """

        out = {}
        # scalars first
        for i in range(len(self.scalars)):
            entry = self.scalars[i]
            try:
                val = function(self, entry, **keywargs)
                # bound again in case name has changed
                entry = self.scalars[i]
                out[entry] = val
            except Exception:
                if raise_errors:
                    raise
                else:
                    entry = self.scalars[i]
                    out[entry] = False
        # then sections
        for i in range(len(self.sections)):
            entry = self.sections[i]
            if call_on_sections:
                try:
                    function(self, entry, **keywargs)
                except Exception:
                    if raise_errors:
                        raise
                    else:
                        entry = self.sections[i]
                        out[entry] = False
                # bound again in case name has changed
                entry = self.sections[i]
            # previous result is discarded
            out[entry] = self[entry].walk(
                function,
                raise_errors=raise_errors,
                call_on_sections=call_on_sections,
                **keywargs)
        return out