def find_environment_variable_value(self, env_variable):
    command = ('${%s}' % str(env_variable))
    if self.environment_values:
        replacement = self.environment_values.get(env_variable)
        if ((not replacement) and (type(replacement) is str)):
            replacement = "''"
        return (replacement if replacement else command)
    return command
def find_environment_variable_value(self, env_variable):
    command = ('${%s}' % str(env_variable))
    if self.environment_values:
        replacement = self.environment_values.get(env_variable)
        if ((not replacement) and (type(replacement) is str)):
            replacement = 
        return (replacement if replacement else command)
    return command