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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 port_channel_minimum_links(self, **kwargs):
 """Set minimum number of links in a port channel. Args: name (str):
 Port-channel number. (1, 5, etc) minimum_links (str):
 Minimum number of links in channel group. callback (function):
 A function executed upon completion of the method. The only parameter passed to `callback` will be the ``ElementTree`` `config`. Returns: Return value of `callback`. Raises: KeyError: if `name` or `minimum_links` is not specified. ValueError: if `name` is not a valid value. Examples: Traceback (most recent call last):
 KeyError """

        name = str(kwargs.pop('name'))
        minimum_links = str(kwargs.pop('minimum_links'))
        callback = kwargs.pop('callback', self._callback)

        min_links_args = dict(name=name, minimum_links=minimum_links)

        if not pynos.utilities.valid_interface('port_channel', name):
            raise ValueError("`name` must match `^[0-9]{1,3}${1,3}$`")

        config = getattr(
            self._interface,
            'interface_port_channel_minimum_links'
        )(**min_links_args)

        return callback(config)