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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 _GetFileSystemCacheIdentifier(self, path_spec):
 """Determines the file system cache identifier for the path specification. Args: path_spec (PathSpec):
 path specification. Returns: str: identifier of the VFS object. """

    string_parts = []

    string_parts.append(getattr(path_spec.parent, 'comparable', ''))
    string_parts.append('type: {0:s}'.format(path_spec.type_indicator))

    return ''.join(string_parts)