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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 help_text(cls):
 """Return a slack-formatted list of commands with their usage."""

        docs = [cmd_func.__doc__ for cmd_func in cls.commands.values()]

        # Don't want to include 'usage: ' or explanation.
        usage_lines = [doc.partition('\n')[0] for doc in docs]
        terse_lines = [line[len('Usage: '):] for line in usage_lines]
        terse_lines.sort()
        return '\n'.join(['Available commands:\n'] + terse_lines)