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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 iter_following(username, number=-1, etag=None):
 """List the people ``username`` follows. :param str username: (required), login of the user :param int number: (optional), number of users being followed by username to return. Default: -1, return all of them :param str etag: (optional), ETag from a previous request to the same endpoint :returns: generator of :class:`User <github3.users.User>` """

    return gh.iter_following(username, number, etag) if username else []