qgis plugins - How can I access to elements in dir(some_class) of PyQGIS without a dictionary in my code?

I'm developing a QGIS plugin to search class methods in the different classes of PyQGIS. I used three widgets: 2 objects of type QLineEdit (for classes and class methods) and one QTextBrowser (for results). The snipped code is below:

.
.
.
    def run(self):
        """Run method that performs all the real work"""

        text_search_class = self.dlg.lineEdit.text()
        text_search_line = self.dlg.lineEdit2.text()

        dict = {'QgsVectorLayer' : dir(QgsVectorLayer) 

                'QgsRasterLayer' : dir(QgsRasterLayer),
                'QLineEdit'      : dir(QLineEdit)}

        if ( text_search_class in dict.keys() ) == True:

            idx = dict.keys().index(text_search_class)

            elements = getPat2(text_search_line, dict.values()[idx])

            n = len(elements)

            message = str(n) + " elements of '" + text_search_line + "' in " + text_search_class + "\n\n" 

            for i in range(n - 1):
                message += elements[i] + ', '

            if n != 0:
                message += elements[n - 1]

            txtBox = self.dlg.textFeedback
            txtBox.setText(message)

        else:
            message = "The chosen class does not exist"
            txtBox = self.dlg.textFeedback
            txtBox.setText(message)

        # show the dialog
        self.dlg.show()
        # Run the dialog event loop
        result = self.dlg.exec_()
        # See if OK was pressed

        if result:
            # Do something useful here - delete the line containing pass and
            # substitute with your code.
            pass

My issue is that I had to use a dictionary to get the list of methods from dir(class) (in my code I only use QgsVectorLayer, QgsRasterLayer and QLineEdit; but they are more than 1200) because, for example, the true list is for dir(QgsVectorLayer); not for dir('QgsVectorLayer') when I don't use the dictionary. My question is how can I access to elements in dir(some_class) of PyQGIS without a dictionary.

The next pictures show the execution of the plugin.

Without any text to search:

Searching by pending, set y max, respectively, in QgsVectorLayer, QgsRasterLayer and QLineEdit:

Answer

The solution to this issue was here:

https://stackoverflow.com/questions/295058/convert-a-string-to-preexisting-variable-names/295113#295113

The keys words were in the title: "Convert a string to preexisting variable names".

My new code is now:

.
.
.
    def run(self):

        """Run method that performs all the real work"""

        text_search_class = self.dlg.lineEdit.text()
        text_search_line = self.dlg.lineEdit2.text()

        try:

            elements = getPat2(text_search_line, dir(globals()[text_search_class]))

            n = len(elements)


            message = str(n) + " elements of '" + text_search_line + "' in " + text_search_class + "\n\n" 

            for i in range(n - 1):
                message += elements[i] + ', '

            if n != 0:
                message += elements[n - 1]

            txtBox = self.dlg.textFeedback

            txtBox.setText(message)

        except KeyError:
            message = "The chosen class does not exist"
            txtBox = self.dlg.textFeedback
            txtBox.setText(message)

        # show the dialog
        self.dlg.show()
        # Run the dialog event loop

        result = self.dlg.exec_()
        # See if OK was pressed
        if result:
            # Do something useful here - delete the line containing pass and
            # substitute with your code.
            pass

The next pictures show the execution of the plugin with the new classes extracted with globals() (without a dictionary):