def add_to(<EOL>self, to_email, global_substitutions=None, is_multiple=False, p=<NUM_LIT:0>):
if isinstance(to_email, list):<EOL><INDENT>for email in to_email:<EOL><INDENT>if isinstance(email, str):<EOL><INDENT>email = To(email, None)<EOL><DEDENT>if isinstance(email, tuple):<EOL><INDENT>email = To(email[<NUM_LIT:0>], email[<NUM_LIT:1>])<EOL><DEDENT>self._set_emails(email, global_substitutions, is_multiple, p)<EOL><DEDENT><DEDENT>else:<EOL><INDENT>if isinstance(to_email, str):<EOL><INDENT>to_email = To(to_email, None)<EOL><DEDENT>if isinstance(to_email, tuple):<EOL><INDENT>to_email = To(to_email[<NUM_LIT:0>], to_email[<NUM_LIT:1>])<EOL><DEDENT>if isinstance(to_email, Email):<EOL><INDENT>p = to_email.personalization<EOL><DEDENT>self._set_emails(to_email, global_substitutions, is_multiple, p)<EOL><DEDENT>
Adds a To object to the Personalization object

        :param to_emails: A To object
        :type to_emails: To, str, tuple
        :param global_substitutions: A dict of substitutions for all recipients
        :type global_substitutions: dict
        :param is_multiple: Create a new personilization for each recipient
        :type is_multiple: bool
        :param p: p is the Personalization object or Personalization object
                  index
        :type p: Personalization, integer, optional