docs: def check_python_modules():
      """Check if all necessary / recommended modules are installed."""
      print("\033[1mCheck modules\033[0m")
      required_modules = ['argparse', 'matplotlib', 'natsort', 'pymysql',
                          'cPickle', 'theano', 'dropbox', 'yaml',
                          'webbrowser', 'hashlib', 'numpy',
                          'jinja2']
      found = []
      for required_module in required_modules:
          try:
              imp.find_module(required_module)
              check = "module '%s' ... %sfound%s" % (required_module,
                                                     Bcolors.OKGREEN,
                                                     Bcolors.ENDC)
              print(check)
              found.append(required_module)
          except ImportError:
              print("module '%s' ... %sNOT%s found" % (required_module,
                                                       Bcolors.WARNING,
                                                       Bcolors.ENDC))
  
      if "argparse" in found:
          import argparse
          print("argparse version: %s (1.1 tested)" % argparse.__version__)
      if "matplotlib" in found:
          import matplotlib
          print("matplotlib version: %s (1.2.1 tested)" % matplotlib.__version__)
      if "natsort" in found:
          import natsort
          print("natsort version: %s (3.4.0 tested, 3.4.0 > required)" %
                natsort.__version__)
      if "pymysql" in found:
          import pymysql
          print("pymysql version: %s (0.6.3 tested)" %
                pymysql.__version__)
      if "theano" in found:
          import theano
          print("theano version: %s (0.6.0 tested)" %
                theano.__version__)
      if "numpy" in found:
          import numpy
          print("numpy version: %s (1.8.1 tested)" %
                numpy.__version__)
      if "yaml" in found:
          import yaml
          print("yaml version: %s (3.11 tested)" %
                yaml.__version__)
      if "jinja2" in found:
          import jinja2
          print("jinja2 version: %s (2.7.3 tested)" %
                jinja2.__version__)
      if "cPickle" in found:
          import cPickle
          print("cPickle version: %s (1.71 tested)" %
                cPickle.__version__)
          print("cPickle HIGHEST_PROTOCOL: %s (2 required)" %
                cPickle.HIGHEST_PROTOCOL)