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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 check_dependencies():
 """Make sure virtualenv is in the path."""


    print 'Checking dependencies...'
    if not HAS_VIRTUALENV:
        print 'Virtual environment not found.'
        # Try installing it via easy_install...
        if HAS_EASY_INSTALL:
            print 'Installing virtualenv via easy_install...',
            run_command(['easy_install', 'virtualenv'],
                        die_message='easy_install failed to install virtualenv'
                                    '\ndevelopment requires virtualenv, please'
                                    ' install it using your favorite tool')
            if not run_command(['which', 'virtualenv']):
                die('ERROR: virtualenv not found in path.\n\ndevelopment '
                    ' requires virtualenv, please install it using your'
                    ' favorite package management tool and ensure'
                    ' virtualenv is in your path')
            print 'virtualenv installation done.'
        else:
            die('easy_install not found.\n\nInstall easy_install'
                ' (python-setuptools in ubuntu) or virtualenv by hand,'
                ' then rerun.')
    print 'dependency check done.'