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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 listdir(self, name, **kwargs):
 """ Returns a list of the files under the specified path. This is different from list as it will only give you files under the current directory, much like ls. name must be in the form of `s3://bucket/prefix/` Parameters keys: optional if True then this will return the actual boto keys for files that are encountered objects: optional if True then this will return the actual boto objects for files or prefixes that are encountered """

        assert self._is_s3(name), "name must be in form s3://bucket/prefix/"

        if not name.endswith('/'):
            name += "/"
        return self.list(name, delimiter='/', **kwargs)