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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 user_has_email(username):
 """ make sure, that given user has an email associated """

    user = api.user.get(username=username)
    if not user.getProperty("email"):
        msg = _(
            "This user doesn't have an email associated "
            "with their account."
        )
        raise Invalid(msg)

    return True