Do the hard work for readmodule[_ex].

    If INPACKAGE is given, it must be the dotted name of the package in
    which we are searching for a submodule, and then PATH must be the
    package search path; otherwise, we are searching for a top-level
    module, and PATH is combined with sys.path.

def _readmodule(module, path, inpackage=None):
    '''Do the hard work for readmodule[_ex].

    If INPACKAGE is given, it must be the dotted name of the package in
    which we are searching for a submodule, and then PATH must be the
    package search path; otherwise, we are searching for a top-level
    module, and PATH is combined with sys.path.
    '''
    # Compute the full module name (prepending inpackage if set)
    if inpackage is not None:
        fullmodule = "%s.%s" % (inpackage, module)
    else:
        fullmodule = module

    # Check in the cache
    if fullmodule in _modules:
        return _modules[fullmodule]

    # Initialize the dict for this module's contents
    dict = OrderedDict()

    # Check if it is a built-in module; we don't do much for these
    if module in sys.builtin_module_names and inpackage is None:
        _modules[module] = dict
        return dict

    # Check for a dotted module name
    i = module.rfind('.')
    if i >= 0:
        package = module[:i]
        submodule = module[i + 1:]
        parent = _readmodule(package, path, inpackage)
        if inpackage is not None:
            package = "%s.%s" % (inpackage, package)
        return _readmodule(submodule, parent['__path__'], package)

    # Search the path for the module
    f = None
    if inpackage is not None:
        f, fname, (_s, _m, ty) = imp.find_module(module, path)
    else:
        f, fname, (_s, _m, ty) = imp.find_module(module, path + sys.path)
    if ty == imp.PKG_DIRECTORY:
        dict['__path__'] = [fname]
        path = [fname] + path
        f, fname, (_s, _m, ty) = imp.find_module('__init__', [fname])
    _modules[fullmodule] = dict
    if ty != imp.PY_SOURCE:
        # not Python source, can't do anything with this module
        f.close()
        return dict

    stack = []  # stack of (class, indent) pairs

    g = tokenize.generate_tokens(f.readline)
    try:
        for tokentype, token, start, _end, _line in g:
            if tokentype == DEDENT:
                lineno, thisindent = start
                # close nested classes and defs
                while stack and stack[-1][1] >= thisindent:
                    del stack[-1]
            elif token == 'def':
                lineno, thisindent = start
                # close previous nested classes and defs
                while stack and stack[-1][1] >= thisindent:
                    del stack[-1]
                tokentype, meth_name, start = g.next()[0:3]
                if tokentype != NAME:
                    continue  # Syntax error
                if stack:
                    cur_class = stack[-1][0]
                    if isinstance(cur_class, Class):
                        # it's a method
                        cur_class._addmethod(meth_name, lineno)
                        # else it's a nested def
                else:
                    # it's a function
                    dict[meth_name] = Function(fullmodule, meth_name,
                                               fname, lineno)
                stack.append((None, thisindent))  # Marker for nested fns
            elif token == 'class':
                lineno, thisindent = start
                # close previous nested classes and defs
                while stack and stack[-1][1] >= thisindent:
                    del stack[-1]
                tokentype, class_name, start = g.next()[0:3]
                if tokentype != NAME:
                    continue  # Syntax error
                # parse what follows the class name
                tokentype, token, start = g.next()[0:3]
                inherit = None
                if token == '(':
                    names = []  # List of superclasses
                    # there's a list of superclasses
                    level = 1
                    super = []  # Tokens making up current superclass
                    while True:
                        tokentype, token, start = g.next()[0:3]
                        if token in (')', ',') and level == 1:
                            n = "".join(super)
                            if n in dict:
                                # we know this super class
                                n = dict[n]
                            else:
                                c = n.split('.')
                                if len(c) > 1:
                                    # super class is of the form
                                    # module.class: look in module for
                                    # class
                                    m = c[-2]
                                    c = c[-1]
                                    if m in _modules:
                                        d = _modules[m]
                                        if c in d:
                                            n = d[c]
                            names.append(n)
                            super = []
                        if token == '(':
                            level += 1
                        elif token == ')':
                            level -= 1
                            if level == 0:
                                break
                        elif token == ',' and level == 1:
                            pass
                        # only use NAME and OP (== dot) tokens for type name
                        elif tokentype in (NAME, OP) and level == 1:
                            super.append(token)
                            # expressions in the base list are not supported
                    inherit = names
                cur_class = Class(fullmodule, class_name, inherit,
                                  fname, lineno)
                if not stack:
                    dict[class_name] = cur_class
                stack.append((cur_class, thisindent))
            elif token == 'import' and start[1] == 0:
                modules = _getnamelist(g)
                for mod, _mod2 in modules:
                    try:
                        # Recursively read the imported module
                        if inpackage is None:
                            _readmodule(mod, path)
                        else:
                            try:
                                _readmodule(mod, path, inpackage)
                            except ImportError:
                                _readmodule(mod, [])
                    except:
                        # If we can't find or parse the imported module,
                        # too bad -- don't die here.
                        pass
            elif token == 'from' and start[1] == 0:
                mod, token = _getname(g)
                if not mod or token != "import":
                    continue
                names = _getnamelist(g)
                try:
                    # Recursively read the imported module
                    d = _readmodule(mod, path, inpackage)
                except:
                    # If we can't find or parse the imported module,
                    # too bad -- don't die here.
                    continue
                # add any classes that were defined in the imported module
                # to our name space if they were mentioned in the list
                for n, n2 in names:
                    if n in d:
                        dict[n2 or n] = d[n]
                    elif n == '*':
                        # don't add names that start with _
                        for n in d:
                            if n[0] != '_':
                                dict[n] = d[n]
            elif tokentype == NAME and start[1] == 0:
                name = token
                line = _line
                tokentype, token = g.next()[0:2]
                if tokentype == OP and token == "=":
                    dict[name] = Global(fullmodule, name, fname, _line)
    except StopIteration:
        pass

    f.close()
    return dict