st.get_option(key)
st.set_option(key, value)
st.set_page_config(layout='wide')
```
Optimize performance
Legacy caching
```python
@st.cache
... def foo(bar):
...   # Do something expensive in here...
...   return data
Executes foo
d1 = foo(ref1)
Does not execute foo
Returns cached item by reference, d1 == d2
d2 = foo(ref1)
Different arg, so function foo executes
d3 = foo(ref2)
```
Cache data objects
```python
E.g. Dataframe computation, storing downloaded data, etc.
@st.experimental_memo
... def foo(bar):
...   # Do something expensive and return data
...   return data
Executes foo
d1 = foo(ref1)
Does not execute foo
Returns cached item by value, d1 == d2
d2 = foo(ref1)
Different arg, so function foo executes
d3 = foo(ref2)
```
Cache non-data objects
```python
E.g. TensorFlow session, database connection, etc.
