title: Plot NETCDF data only for the area of interest in python?
body: <p>below is my code to plot data from a netcdf file.
  However, I can plot the data with the basemap for the whole world.
  I insert the xxxxxx shapefile through the basemap module and my goal is to plot to a specific area</p>
  
  <pre><code>### Import libraries###
  
  import matplotlib.pyplot as plt 
  from mpl_toolkits.basemap import Basemap
  from netCDF4 import Dataset
  import numpy as np
  
  
  ### opening NETCDF dataset MERRA###
  
  file = 'C:.../Python_Notebook/NETCDF/MERRA2_400.statD_2d_slv_Nx.20190101.nc4'
  fh = Dataset(file, mode = 'r')
  
  
  ### Get variables ###
  # Read in 'T2M' 2-meter air temperature variable.
  lons = fh.variables['lon'][:] # get longitude variables
  lats = fh.variables['lat'][:] # get latitude variables
  tmean = fh.variables['T2MMEAN'][:,:,:] - 273.15 # get tmean variable with conversion K for °C 
  
  ### meshgrid ###
  
  m=Basemap(projection='cyl',llcrnrlat=-20,urcrnrlat=-5,llcrnrlon=-63,urcrnrlon=-48)
  lon, lat = np.meshgrid(lons, lats) # create a matrix of coordinates
  xi, yi = m(lon, lat)
  
  # Plot Data
  
  fig,ax=plt.subplots(figsize=(20,10))
  cs = m.contourf(xi,yi,np.squeeze(tmean),  cmap='rainbow') 
  
  ### Draw ### 
  m.readshapefile(MTshp, name="Mt") # draw shapefile State of Mato Grosso Brazil
  #m.drawcoastlines()
  #m.drawcountries()
  #m.drawstates()
  
  ### Draw Coordinates ###
  
  m.drawparallels(np.arange(-80, 80, 5), labels=[1,0,0,0]) # draw parallels
  m.drawmeridians(np.arange(-180, 180, 5), labels=[0,0,0,1]) # draw meridians
  
  # Add Colorbar
  cbar = m.colorbar(cs, location='right', pad="15%")
  cbar.set_label('°C') # tmean units
  
  ### Labels ###
  plt.xlabel('Longitude', fontweight='bold', labelpad=15)
  plt.ylabel('Latitude', fontweight='bold', labelpad=25)
  
  ### Add Title ###
  plt.title('01-01-2019 Mean Temperature', fontweight='bold', fontsize=12)
  
  # Show the plot
  plt.show()
  </code></pre>
  
  <p>what should i do to plot the netcdf data only in my shapefile?
  what procedure should i do?
  can you help me? please?
  I thank you for your understanding</p>