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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 build_pypackage_basename(self, pytree, base):
 """Build the string representing the parsed package basename. :param str pytree: The pytree absolute path. :param str pytree: The absolute path of the pytree sub-package of which determine the parsed name. :rtype: str """

        dirname = os.path.dirname(pytree)
        parsed_package_name = base.replace(dirname, '').strip('/')
        return parsed_package_name