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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 get_account_metadata(self, prefix=None):
 """ Returns a dictionary containing metadata about the account. """

        headers = self.get_account_headers()
        if prefix is None:
            prefix = ACCOUNT_META_PREFIX
        low_prefix = prefix.lower()
        ret = {}
        for hkey, hval in list(headers.items()):
            lowkey = hkey.lower()
            if lowkey.startswith(low_prefix):
                cleaned = hkey.replace(low_prefix, "").replace("-", "_")
                ret[cleaned] = hval
        return ret