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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 remove_user(username):
 """ Remove user, his home directory and so on.. Args: username (str):
 User's name. """

    users = passwd_reader.load_users()

    assert username in users, "Username '%s' not found!" % username

    # remove user from passwd file
    del users[username]
    passwd_reader.save_users(users)

    # remove home directory
    home_dir = settings.DATA_PATH + username
    if os.path.exists(home_dir):
        shutil.rmtree(home_dir)

    reload_configuration()