# 3.23 `codeop` -- Compile Python code

The `codeop` module provides a function to compile Python code with hints on whether it is certainly complete, possibly complete or definitely incomplete. This is used by the `code` module and should not normally be used directly.

The `codeop` module defines the following function:

`compile_command`(source[, filename[, symbol]])
  Tries to compile source, which should be a string of Python code and return a code object if source is valid Python code. In that case, the filename attribute of the code object will be filename, which defaults to `'<input>'`. Returns `None` if source is not valid Python code, but is a prefix of valid Python code.

  If there is a problem with source, an exception will be raised. `SyntaxError` is raised if there is invalid Python syntax, and `OverflowError` if there is an invalid numeric constant.

  The symbol argument determines whether source is compiled as a statement (`'single'`, the default) or as an expression (`'eval'`). Any other value will cause `ValueError` to be raised.

  Caveat: It is possible (but not likely) that the parser stops parsing with a successful outcome before reaching the end of the source; in this case, trailing symbols may be ignored instead of causing an error. For example, a backslash followed by two newlines may be followed by arbitrary garbage. This will be fixed once the API for the parser is better.