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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 savemat(file_name, mdict, appendmat=True, format='7.3', oned_as='row', store_python_metadata=True, action_for_matlab_incompatible='error', marshaller_collection=None, truncate_existing=False, truncate_invalid_matlab=False, **keywords):
 """ Save a dictionary of python types to a MATLAB MAT file. Saves the data provided in the dictionary `mdict` to a MATLAB MAT file. `format` determines which kind/vesion of file to use. The '7.3' version, which is HDF5 based, is handled by this package and all types that this package can write are supported. Versions 4 and 5 are not HDF5 based, so everything is dispatched to the SciPy package's ``scipy.io.savemat`` function, which this function is modelled after (arguments not specific to this package have the same names, etc.). Parameters file_name : str or file-like object Name of the MAT file to store in. The '.mat' extension is added on automatically if not present if `appendmat` is set to ``True``. An open file-like object can be passed if the writing is being dispatched to SciPy (`format` < 7.3). mdict : dict The dictionary of variables and their contents to store in the file. appendmat : bool, optional Whether to append the '.mat' extension to `file_name` if it doesn't already end in it or not. format : {'4', '5', '7.3'}, optional The MATLAB mat file format to use. The '7.3' format is handled by this package while the '4' and '5' formats are dispatched to SciPy. oned_as : {'row', 'column'}, optional Whether 1D arrays should be turned into row or column vectors. store_python_metadata : bool, optional Whether or not to store Python type information. Doing so allows most types to be read back perfectly. Only applicable if not dispatching to SciPy (`format` >= 7.3). action_for_matlab_incompatible: str, optional The action to perform writing data that is not MATLAB compatible. The actions are to write the data anyways ('ignore'), don't write the incompatible data ('discard'), or throw a ``TypeNotMatlabCompatibleError`` exception. marshaller_collection : MarshallerCollection, optional Collection of marshallers to disk to use. Only applicable if not dispatching to SciPy (`format` >= 7.3). truncate_existing : bool, optional Whether to truncate the file if it already exists before writing to it. truncate_invalid_matlab : bool, optional Whether to truncate a file if the file doesn't have the proper header (userblock in HDF5 terms) setup for MATLAB metadata to be placed. **keywords : Additional keywords arguments to be passed onto ``scipy.io.savemat`` if dispatching to SciPy (`format` < 7.3). Raises ------ ImportError If `format` < 7.3 and the ``scipy`` module can't be found. NotImplementedError If writing a variable in `mdict` is not supported. exceptions.TypeNotMatlabCompatibleError If writing a type not compatible with MATLAB and `action_for_matlab_incompatible` is set to ``'error'``. Notes ----- Writing the same data and then reading it back from disk using the HDF5 based version 7.3 format (the functions in this package) or the older format (SciPy functions) can lead to very different results. Each package supports a different set of data types and converts them to and from the same MATLAB types differently. See Also -------- loadmat : Equivelent function to do reading. scipy.io.savemat : SciPy function this one models after and dispatches to. Options writes : Function used to do the actual writing. """

    # If format is a number less than 7.3, the call needs to be
    # dispatched to the scipy version, if it is available, with all the
    # relevant and extra keywords options provided.
    if float(format) < 7.3:
        import scipy.io
        scipy.io.savemat(file_name, mdict, appendmat=appendmat,
                         format=format, oned_as=oned_as, **keywords)
        return

    # Append .mat if it isn't on the end of the file name and we are
    # supposed to.
    if appendmat and not file_name.endswith('.mat'):
        file_name = file_name + '.mat'

    # Make the options with matlab compatibility forced.
    options = Options(store_python_metadata=store_python_metadata, \
        matlab_compatible=True, oned_as=oned_as, \
        action_for_matlab_incompatible=action_for_matlab_incompatible, \
        marshaller_collection=marshaller_collection)

    # Write the variables in the dictionary to file.
    writes(mdict=mdict, filename=file_name,
           truncate_existing=truncate_existing,
           truncate_invalid_matlab=truncate_invalid_matlab,
           options=options)