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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 _is_present(val):
 """Returns True if the value is not None, and if it is either not a string, or a string with length > 0. """

    if val is None:
      return False
    if isinstance(val, str):
      return len(val) > 0
    return True