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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 prep_shell_environment(nova_env, nova_creds):
 """ Appends new variables to the current shell environment temporarily. """

    new_env = {}

    for key, value in prep_nova_creds(nova_env, nova_creds):
        if type(value) == six.binary_type:
            value = value.decode()
        new_env[key] = value

    return new_env