Introspection

• type() returns the class of an object

• hasattr() / getattr() / setattr to query / get / set a property

• issubclass()

for (n, v) in myobj.__dict__.items(): print "%s: %s" % (n, v)

Import-Hook

import __builtin__
old_import = __builtin__.__import__
known_imports = []

def import_hook(name, globals=None, locals=None, fromlist=None):
    if name.startswith("django_chuck") and name not in known_imports:
        if fromlist:
            for symbol in fromlist:
                print name + "." + symbol
                known_imports.append(name + "." + symbol)
        else:
            print name
            known_imports.append(name)

    return old_import(name, globals, locals, fromlist)

__builtin__.__import__ = import_hook

Inrospect imports with compiler

# code borrowed from zope
class ImportFinder:
    def __init__(self):
        self.imports = []

    def visitFrom(self, statement):
        stmt = statement.asList()
        if stmt[0] == '__future__':
            # we don't care what's imported from the future
            return
        names_dict = {}

        for orig_name, as_name in stmt[1]:
            # we don't care about from import *
            if orig_name == '*':
                continue

            self.imports.append(stmt[0] + "." + orig_name)

    def visitImport(self, stmt):
        for orig_name, as_name in stmt.names:
            self.imports.append(orig_name)

ast = compiler.parseFile("django_chuck/commands/create_project.py")
log = ImportFinder()
compiler.walk(ast, log)
print log.imports