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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 find_defined_levels():
 """ Find the defined logging levels. :returns: A dictionary with level names as keys and integers as values. Here's what the result looks like by default (when no custom levels or level names have been defined):
 {'NOTSET': 0, 'DEBUG': 10, 'INFO': 20, 'WARN': 30, 'WARNING': 30, 'ERROR': 40, 'FATAL': 50, 'CRITICAL': 50} """

    defined_levels = {}
    for name in dir(logging):
        if name.isupper():
            value = getattr(logging, name)
            if isinstance(value, int):
                defined_levels[name] = value
    return defined_levels