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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 username(elk, user_number):
 """Return name of user."""

    if user_number >= 0 and user_number < elk.users.max_elements:
        return elk.users[user_number].name
    if user_number == 201:
        return "*Program*"
    if user_number == 202:
        return "*Elk RP*"
    if user_number == 203:
        return "*Quick arm*"
    return ""