how matplotlib in pyqt5 using qt designer

Question

I am trying to put a matplotlib plot (with tool bar) in a pyqt5 window, but I am unable to put the plot with the toolbar and associate it to a qwidget. I made the interface using the qt designer and converted it to a py file I can open the window, but the size is wrong and it has no toolbar. can someone help me 'force' a matplotlib window into pyqt?

this is the converted file, I want to 'add' the matplotlib plot to the widget named "mplwindow"

# -*- coding: utf-8 -*-

# Form implementation generated from reading ui file 'GUI.ui'
#
# Created by: PyQt5 UI code generator 5.13.1
#
# WARNING! All changes made in this file will be lost!


from PyQt5 import QtCore, QtGui, QtWidgets


class Ui_MainWindow(object):
    def setupUi(self, MainWindow):
        MainWindow.setObjectName("MainWindow")
        MainWindow.resize(800, 600)
        self.centralwidget = QtWidgets.QWidget(MainWindow)
        self.centralwidget.setObjectName("centralwidget")
        self.gridLayout = QtWidgets.QGridLayout(self.centralwidget)
        self.gridLayout.setObjectName("gridLayout")
        self.mplwindow = QtWidgets.QWidget(self.centralwidget)
        sizePolicy = QtWidgets.QSizePolicy(QtWidgets.QSizePolicy.Expanding, QtWidgets.QSizePolicy.Preferred)
        sizePolicy.setHorizontalStretch(0)
        sizePolicy.setVerticalStretch(0)
        sizePolicy.setHeightForWidth(self.mplwindow.sizePolicy().hasHeightForWidth())
        self.mplwindow.setSizePolicy(sizePolicy)
        self.mplwindow.setObjectName("mplwindow")
        self.mplvl = QtWidgets.QVBoxLayout(self.mplwindow)
        self.mplvl.setObjectName("mplvl")
        self.gridLayout.addWidget(self.mplwindow, 0, 0, 1, 1)
        self.mplfigs = QtWidgets.QListWidget(self.centralwidget)
        self.mplfigs.setMinimumSize(QtCore.QSize(0, 0))
        self.mplfigs.setMaximumSize(QtCore.QSize(200, 16777215))
        self.mplfigs.setObjectName("mplfigs")
        self.gridLayout.addWidget(self.mplfigs, 0, 1, 1, 1)
        MainWindow.setCentralWidget(self.centralwidget)
        self.menubar = QtWidgets.QMenuBar(MainWindow)
        self.menubar.setGeometry(QtCore.QRect(0, 0, 800, 26))
        self.menubar.setObjectName("menubar")
        MainWindow.setMenuBar(self.menubar)
        self.statusbar = QtWidgets.QStatusBar(MainWindow)
        self.statusbar.setObjectName("statusbar")
        MainWindow.setStatusBar(self.statusbar)

        self.retranslateUi(MainWindow)
        QtCore.QMetaObject.connectSlotsByName(MainWindow)

    def retranslateUi(self, MainWindow):
        _translate = QtCore.QCoreApplication.translate
        MainWindow.setWindowTitle(_translate("MainWindow", "MainWindow"))

here is my main file: import numpy as np import random

import sys
from test_ui import Ui_MainWindow
from PyQt5.QtWidgets import QApplication, QMainWindow, QSizePolicy
from matplotlib.backends.backend_qt5agg import FigureCanvasQTAgg as FigureCanvas
from matplotlib.figure import Figure
import matplotlib.pyplot as plt


class mywindow(QMainWindow):

    def __init__(self):
        super(mywindow, self).__init__()
        self.ui = Ui_MainWindow()
        self.ui.setupUi(self)

        # test data
        data = np.array([0.7, 0.7, 0.7, 0.8, 0.9, 0.9, 1.5, 1.5, 1.5, 1.5])
        fig, ax1 = plt.subplots()
        bins = np.arange(0.6, 1.62, 0.02)
        n1, bins1, patches1 = ax1.hist(data, bins, alpha=0.6, density=False, cumulative=False)
        # plot

        self.ui.mplwindow = PlotCanvas(self)


class PlotCanvas(FigureCanvas):

    def __init__(self, parent=None):
        fig = Figure()
        self.axes = fig.add_subplot(111)

        FigureCanvas.__init__(self, fig)
        self.setParent(parent)

        FigureCanvas.setSizePolicy(self,
                QSizePolicy.Expanding,
                QSizePolicy.Expanding)
        FigureCanvas.updateGeometry(self)
        self.plot()


    def plot(self):
        data = [random.random() for i in range(25)]
        ax = self.figure.add_subplot(111)
        ax.plot(data, 'r-')
        ax.set_title('PyQt Matplotlib Example')
        self.draw()


if __name__ == '__main__':

    app = QApplication(sys.argv)
    window = mywindow()
    window.show()
    sys.exit(app.exec_())