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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 authorize(self, scheme, **params):
 """Store credentials required to satisfy a given auth scheme. Args: scheme (str):
 The name of the Authentication scheme. **params: parameters for the specified scheme. Returns: True if parameters are set successfully (note that this doesn't mean the credentials are valid) False if the scheme specified is not supported """

        if scheme not in self.schemes:
            return False

        for field, value in iteritems(params):
            setattr(self, field, value)
            if field in self.schemes[scheme][u'params'].keys() and value:
                self.schemes[scheme][u'params'][field] = value

        return True