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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 alter_subprocess_kwargs_by_platform(**kwargs):

 """
 Given a dict, populate kwargs to create a generally
 useful default setup for running subprocess processes
 on different platforms. For example, `close_fds` is
 set on posix and creation of a new console window is
 disabled on Windows.
 
 This function will alter the given kwargs and return
 the modified dict.
 """

    kwargs.setdefault('close_fds', os.name == 'posix')
    if os.name == 'nt':
        CONSOLE_CREATION_FLAGS = 0  # Default value
        # See: https://msdn.microsoft.com/en-us/library/windows/desktop/ms684863%28v=vs.85%29.aspx
        CREATE_NO_WINDOW = 0x08000000
        # We "or" them together
        CONSOLE_CREATION_FLAGS |= CREATE_NO_WINDOW
        kwargs.setdefault('creationflags', CONSOLE_CREATION_FLAGS)
    return kwargs