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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_curve(self, mnemonic, alias=None):
 """ Wraps get_mnemonic. Instead of picking curves by name directly from the data dict, you can pick them up with this method, which takes account of the alias dict you pass it. If you do not pass an alias dict, then you get the curve you asked for, if it exists, or None. NB Wells do not have alias dicts, but Projects do. Args: mnemonic (str):
 the name of the curve you want. alias (dict):
 an alias dictionary, mapping mnemonics to lists of mnemonics. Returns: Curve. """

        return self.data.get(self.get_mnemonic(mnemonic, alias=alias), None)