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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 authentication_validation(username, password, access_token):
    '''
    Only accept one form of authentication.
    '''
    if bool(username) is not bool(password):
        raise Exception("Basic authentication requires a username AND"
                        " password.")
    if (username and access_token) or (password and access_token):
        raise Exception("Cannot use both Basic Authentication and"
                        " OAuth2.0. Please use only one authentication"
                        " method.")