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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 is_valid_channel(self, channel, conda_url='https://conda.anaconda.org', non_blocking=True):
 """Check if a conda channel is valid."""

        logger.debug(str((channel, conda_url)))
        if non_blocking:
            method = self._is_valid_channel
            return self._create_worker(method, channel, conda_url)
        else:
            return self._is_valid_channel(channel, conda_url=conda_url)