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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 _getsender():
 """Return local sender. Don't use the getpass module, it looks at various environment variables and is unreliable. """

    import os
    import pwd
    import socket
    host = socket.gethostname()
    user = pwd.getpwuid(os.getuid())[0]
    return "%s@%s" % (user, host)