punctuation">,</span><span class="name builtin">input</span><span class="operator">=</span><span class="name builtin pseudo">True</span><span class="punctuation">)])</span>
</pre>
<p><strong>If input is set to True</strong> the variable update will be ignored if the variable is defined in parent environment. If variable is not defined in parent environment, it will be defined and set to value from the command.
<strong>If input is set to False</strong> update will overwrite variable value if variable exists,