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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 getCustomLogger(name, logLevel, logFormat='%(asctime)s %(levelname)-9s:%(name)s:%(module)s:%(funcName)s: %(message)s'):
  '''
  Set up logging

  :param str name: What log level to set
  :param str logLevel: What log level to use
  :param str logFormat: Format string for logging
  :rtype: logger
  '''
  assert isinstance(logFormat, basestring), ("logFormat must be a string but is %r" % logFormat)
  assert isinstance(logLevel, basestring), ("logLevel must be a string but is %r" % logLevel)
  assert isinstance(name, basestring), ("name must be a string but is %r" % name)

  validLogLevels = ['CRITICAL', 'DEBUG', 'ERROR', 'INFO', 'WARNING']

  if not logLevel:
    logLevel = 'DEBUG'

  # If they don't specify a valid log level, err on the side of verbosity
  if logLevel.upper() not in validLogLevels:
    logLevel = 'DEBUG'

  numericLevel = getattr(logging, logLevel.upper(), None)
  if not isinstance(numericLevel, int):
    raise ValueError("Invalid log level: %s" % logLevel)

  logging.basicConfig(level=numericLevel, format=logFormat)
  logger = logging.getLogger(name)
  return logger