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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 wrsamp(self, expanded=False, write_dir=''):
 """ Write a wfdb header file and any associated dat files from this object. Parameters expanded : bool, optional Whether to write the expanded signal (e_d_signal) instead of the uniform signal (d_signal). write_dir : str, optional The directory in which to write the files. """

        # Perform field validity and cohesion checks, and write the
        # header file.
        self.wrheader(write_dir=write_dir)
        if self.n_sig > 0:
            # Perform signal validity and cohesion checks, and write the
            # associated dat files.
            self.wr_dats(expanded=expanded, write_dir=write_dir)