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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 set_context(**options):
 """Set options in the existing context."""

    if not local_context._options:
        raise TelluricContextError("TelluricContext context not exists")
    else:
        local_context._options.update(options)
        log.debug("Updated existing %r with options %r", local_context._options, options)