Client APIs
Function Expression
This expression contains a function call.
It can be constructed by providing the function name and an arbitrary amount of Expressions as arguments.  
```python
import duckdb
import pandas as pd
from duckdb import (
ConstantExpression,
ColumnExpression,
FunctionExpression
)

df = pd.DataFrame({
'a': [
'test',
'pest',
'text',
'rest',
]
})

ends_with = FunctionExpression('ends_with', ColumnExpression('a'), ConstantExpression('est'))
res = duckdb.df(df).select(ends_with).fetchall()
print(res)
# [(True,), (True,), (False,), (True,)]
```