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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 write_conf(self, config_file_type, opener, skip_keys=None):
 """write a configuration file to a file-like object. parameters: config_file_type - a string containing a registered file type OR a for_XXX module from the value_source package. Passing in an string that is unregistered will result in a KeyError opener - a callable object or function that returns a file like object that works as a context in a with statement."""


        blocked_keys = self.keys_blocked_from_output
        if skip_keys:
            blocked_keys.extend(skip_keys)

        if blocked_keys:
            option_defs = self.option_definitions.safe_copy()
            for a_blocked_key in blocked_keys:
                try:
                    del option_defs[a_blocked_key]
                except (AttributeError, KeyError):
                    # okay that key isn't here
                    pass
            # remove empty namespaces
            all_keys = [k for k in
                        option_defs.keys_breadth_first(include_dicts=True)]
            for key in all_keys:
                candidate = option_defs[key]
                if (isinstance(candidate, Namespace) and not len(candidate)):
                    del option_defs[key]
        else:
            option_defs = self.option_definitions

        # find all of the secret options and overwrite their values with
        # '*' * 16
        if not self.option_definitions.admin.expose_secrets.default:
            for a_key in option_defs.keys_breadth_first():
                an_option = option_defs[a_key]
                if (
                    (not a_key.startswith('admin'))
                    and isinstance(an_option, Option)
                    and an_option.secret
                ):
                    # force the option to be a string of *
                    option_defs[a_key].value = '*' * 16
                    option_defs[a_key].from_string_converter = str

        dispatch_request_to_write(config_file_type, option_defs, opener)