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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 start_output (self):
 """ Start log output. """

        # map with spaces between part name and value
        if self.logparts is None:
            parts = Fields.keys()
        else:
            parts = self.logparts
        values = (self.part(x) for x in parts)
        # maximum indent for localized log part names
        self.max_indent = max(len(x) for x in values)+1
        for key in parts:
            numspaces = (self.max_indent - len(self.part(key)))
            self.logspaces[key] = u" " * numspaces
        self.stats.reset()
        self.starttime = time.time()