Should import statements always be at the top of a module?

Question

PEP 08 states:

Imports are always put at the top of the file, just after any module comments and docstrings, and before module globals and constants.<

Answer 1

In addition to the excellent answers already given, it's worth noting that the placement of imports is not merely a matter of style. Sometimes a module has implicit dependencies that need to be imported or initialized first, and a top-level import could lead to violations of the required order of execution.

This issue often comes up in Apache Spark's Python API, where you need to initialize the SparkContext before importing any pyspark packages or modules. It's best to place pyspark imports in a scope where the SparkContext is guaranteed to be available.