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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 get_val(source, extract=None, transform=None):
 """Extract a value from a source, transform and return it."""

  if extract is None:
    raw_value = source
  else:
    raw_value = extract(source)

  if transform is None:
    return raw_value
  else:
    return transform(raw_value)