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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_creation_datetime(filepath):
 """ Get the date that a file was created. Parameters filepath : str Returns ------- creation_datetime : datetime.datetime or None """

    if platform.system() == 'Windows':
        return datetime.fromtimestamp(os.path.getctime(filepath))
    else:
        stat = os.stat(filepath)
        try:
            return datetime.fromtimestamp(stat.st_birthtime)
        except AttributeError:
            # We're probably on Linux. No easy way to get creation dates here,
            # so we'll settle for when its content was last modified.
            return None