Question

Given a string a the form 'package.module.Class', is there any simple way in Python to get the class object directly (assuming the module isn’t yet imported)?

If not, what is the cleanest way to separate the 'package.module' part from the 'Class' part, __import__() the module, and then get the class from that?

Answer 1

import sys
def str_to_obj(astr):
    '''
    str_to_obj('scipy.stats.stats') returns the associated module
    str_to_obj('scipy.stats.stats.chisquare') returns the associated function
    '''
    # print('processing %s'%astr)
    try:
        return globals()[astr]
    except KeyError:
        try:
            __import__(astr)
            mod=sys.modules[astr]
            return mod
        except ImportError:
            module,_,basename=astr.rpartition('.')
            if module:
                mod=str_to_obj(module)
                return getattr(mod,basename)
            else:
                raise