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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_canonical_map(self):
 """Return a mapping of available command names and aliases to their canonical command name. """

        cacheattr = "_token2canonical"
        if not hasattr(self, cacheattr):
            # Get the list of commands and their aliases, if any.
            token2canonical = {}
            cmd2funcname = {}  # use a dict to strip duplicates
            for attr in self.get_names():
                if attr.startswith("do_"): cmdname = attr[3:]
                elif attr.startswith("_do_"): cmdname = attr[4:]
                else:
                    continue
                cmd2funcname[cmdname] = attr
                token2canonical[cmdname] = cmdname
            for cmdname, funcname in cmd2funcname.items():  # add aliases
                func = getattr(self, funcname)
                aliases = getattr(func, "aliases", [])
                for alias in aliases:
                    if alias in cmd2funcname:
                        import warnings
                        warnings.warn("'%s' alias for '%s' command conflicts "
                                      "with '%s' handler" %
                                      (alias, cmdname, cmd2funcname[alias]))
                        continue
                    token2canonical[alias] = cmdname
            setattr(self, cacheattr, token2canonical)
        return getattr(self, cacheattr)