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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def open_fileswitcher_dlg(self):

 """Open file list management dialog box"""

        if not self.tabs.count():
            return
        if self.fileswitcher_dlg is not None and \
          self.fileswitcher_dlg.is_visible:
            self.fileswitcher_dlg.hide()
            self.fileswitcher_dlg.is_visible = False
            return
        self.fileswitcher_dlg = FileSwitcher(self, self, self.tabs, self.data,
                                             ima.icon('TextFileIcon'))
        self.fileswitcher_dlg.sig_goto_file.connect(self.set_stack_index)
        self.fileswitcher_dlg.show()
        self.fileswitcher_dlg.is_visible = True