Construct configuration instance of a package.
- package_name – name of the package
- Ex.: ‘distutils’
- parent_name – name of the parent package
- Ex.: ‘numpy’
- top_path – directory of the toplevel package
- Ex.: the directory where the numpy package source sits
- package_path – directory of package. Will be computed by magic from the
- directory of the caller module if not specified
Ex.: the directory where numpy.distutils is
caller_level – frame level to caller namespace, internal parameter.