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@ -27,7 +27,7 @@ from typing import List, Union, Set
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from relational.rtypes import *
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class Relation (object):
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class Relation:
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'''
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This object defines a relation (as a group of consistent tuples) and operations.
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@ -53,9 +53,9 @@ class Relation (object):
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'''
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__hash__ = None # type: None
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def __init__(self, filename : str = '') -> None:
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def __init__(self, filename: str = '') -> None:
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self._readonly = False
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self.content = set() # type: Set[tuple]
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self.content: Set[tuple] = set()
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if len(filename) == 0: # Empty relation
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self.header = Header([])
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